State retention load control system

ABSTRACT

A device may detect a power removal event, determine whether the power removal event is a local power removal event or a system power removal event, and perform state correction. For example, the device may receive an indication of a state change event turning on the lighting device. The indication may be received from a sensor. For example, the sensor may include a photosensing circuit (e.g., capable of detecting light emission from the lighting device) or the sensor may include a live voltage sensor (e.g., capable of detecting a change in current driven to the lighting device). The device may then determine whether the power removal event is a system power removal event or a local power removal event. If the device determines that the power removal event is a system power removal event, the device may perform state correction (e.g., setting the lighting device to its state prior to the power removal event).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to currently pending U.S. ProvisionalPatent App. No. 62/753,650, filed Oct. 31, 2018, entitled “STATERETENTION LOAD CONTROL SYSTEM;” and is a continuation-in-part ofcurrently pending U.S. patent application Ser. No. 15/641,933, filedJul. 5, 2017, entitled “STATE RETENTION LOAD CONTROL SYSTEM,” whichclaims priority to U.S. Provisional Patent App. No. 62/358,435, filedJul. 5, 2016, each of which are incorporated by reference herein intheir entireties.

BACKGROUND

A user environment, such as a residence or an office building, forexample, may be configured using various types of load control systems.FIG. 1 depicts a user environment 100. The user environment 100 includesa wall-mounted load control device 110 (e.g., a light switch) coupled inseries electrical connection between an AC power source 102 and a lightbulb 112 installed in a ceiling mounted downlight fixture 114. The userenvironment 100 includes a table lamp 124 plugged into an electricalreceptacle 126 that is powered by the AC power source 102. The tablelamp 124 is plugged into an electrical receptacle 126 via electricalplug 120. Light bulb 122 is installed in table lamp 124. Thewall-mounted load control device 110 has an internal mechanical switchthat may be opened and closed in response to actuations of a toggleactuator 116 for turning the light bulb 112 on and off.

The user environment 100 includes a battery-powered handheld remotecontrol device 150 having buttons 152. The battery-powered remotecontrol device 150 transmits RF signals 106 in response to actuations ofone or more of the buttons 152. The light bulb 112 and light bulb 122receive messages (e.g., digital messages) via radio-frequency (RF)signals 106. The RF signals 106 are transmitted by the battery-poweredremote control device 150. In response to the received RF signals, thelight bulb 112 and/or light bulb 122 turn on and off.

The user environment may include a bridge and a smartphone or tablet forcontrolling the light bulbs 112, 122. The bridge transmits RF signals tothe light bulbs 112, 122. The bridge receives Wi-Fi signals from thesmartphone or tablet for controlling the light bulbs 112, 122 andformats the information in the Wi-Fi signals for being received by thelight bulbs 112, 122 on a different protocol.

In user environment 100, a problem arises if power is removed from thelight bulb 112 and/or the light bulb 122. The problem arises whether ornot a bridge is present in the user environment 100. For example, ifpower is removed from the light bulbs and returns to the light bulbs,the light bulbs turn on to a default intensity level (e.g., 100%intensity level). As an example, the light bulb 112 may be set toelectronic off and the light bulb 122 may be set to an intensity levelof eighty percent. Power may intentionally be removed from the lightbulb 112 via an actuation of the toggle actuator 116 to the offposition. As another example, power may unintentionally be removed fromthe light bulb 112 and/or the light bulb 122 due a blackout or abrownout. Upon power being returned to the light bulb 112 and the lightbulb 122, the light bulb 112 and light bulb 122 may present light at thedefault intensity (e.g., an intensity level of 100%). Duringunintentional power removal, it may be undesirable to a user for thelight bulb 112 and light bulb 122 to present light at the defaultintensity. Rather, during an unintentional power removal, the user maydesire that the intensity of the light bulbs be returned to theirrespective pre-power removal states (e.g., electronic off and eightypercent, respectively). For example, during an unintentional powerremoval, a user may not desire the light bulb 112 and/or the light bulb122 to operate at the default state of full intensity when the user isasleep or when the user is away from the user environment 100 for anextended period of time. Accordingly, there is a need for the controlsystem to distinguish between an intentional power removal event (basedon a user action) and an unintentional power removal event (such as ablackout), so that the light bulbs may behave in an expected manner.

In the user environment 100, multiple devices (e.g., the remote controldevice 150 via actuations of the buttons 152, and the load controldevice 110 via actuations of the toggle actuator 116) may control alight source (e.g., the light bulb 112). When multiple devices control asingle light source, distinguishing between an intentional power removalevent and an unintentional power removal event may be difficult.

SUMMARY

A load control system may include control devices for controlling anamount of power provided to an electrical load. The control devices mayinclude an input device and/or a load control device. The load controldevices may be capable of directly controlling an electrical load. Theinput devices may be capable of indirectly controlling the electricalload via the load control device. For example, the load control devicemay be capable of controlling the amount of power provided to theelectrical load based on messages (e.g., digital messages) received fromthe input device and/or another device. The digital messages may includeload control instructions or another indication that causes the loadcontrol device to determine load control instructions for controlling anelectrical load.

The control devices may be powered from a power source (e.g.,alternating-current (AC) or direct-current (DC) power source). If aninadequate amount of power is provided to the control devices, thecontrol devices may stop functioning. An inadequate amount of power mayoccur as a result of a power outage (e.g., a blackout, brownout, orother power loss). For example, during a brownout, a control devicepowered by an AC circuit may be inoperable. Although control devices mayreceive an inadequate amount of electric power as a result of poweroutages, control devices may also, or, alternatively, receive aninadequate amount of power in other ways. For example, control devicesmay receive an inadequate amount of power as a result of a user action,such as the user turning a light switch off that powers control devicesor unplugging a power cord that powers the control devices. Powerremoval events as a result of power outages may be referred to as systempower removal events. Power removal events as a result of user actionsmay be referred to as local power removal events.

A control device may be configured to be controlled to and retain one ormore states (e.g., power states). The control device may include memory.The memory may be volatile and/or non-volatile memory. The memory may beused for saving a power state of the control device. A power state ofthe control devices may include an off power state of the controldevice, an on power state of the control device, an intensity state(e.g., an intensity level) of the control device, a color (e.g., a colortemperature) state of the control device, etc. For example, the controldevice may store in memory that the power state of a control device isan intensity state of eighty-percent. The power state may be recalled ata later time. For example, a prior power state (e.g., a power state of acontrol device prior to a power removal event) may be recalled by thecontrol device after the power removal event ends. For example, after apower removal event, a control device may recall that the prior powerstate of the control device was a particular intensity level, such aseighty-five percent. The control device may recall (e.g., from memorywithin the control device) the prior power state of the control device,for example, when the power removal event ends. A lighting device, forexample, may be set to forty percent prior to a power removal event.Upon the power removal event occurring and the power removal eventending, the control device may recall (e.g., from the memory within thecontrol device) that the prior power state of the lighting device wasforty percent. Thus, upon the power removal event ending, the lightingdevice may function at an intensity of forty percent.

A remote control device (e.g., a remote control device and/or a hubdevice) may detect a power removal event, determine whether the powerremoval event is a local power removal event or a system power removalevent, and perform state correction. For example, the remote controldevice may receive an indication of a state change event turning on alighting device. The indication may be received from a sensor. Forexample, the sensor may include a photosensing circuit (e.g., capable ofdetecting light emission from the lighting device) or the sensor mayinclude a live voltage sensor (e.g., capable of detecting a change incurrent driven to the lighting device). The sensor may be an internalsensor to the remote control device, or an external sensor.

The remote control device may determine whether the power removal eventis a system power removal event or a local power removal event. Forexample, the remote control device may transmit one or more message tothe lighting device to determine whether the power removal event is asystem power removal event or a local power removal event. If the remotecontrol device receives a response from the lighting device, the remotecontrol device may determine that the lighting device is powered (e.g. alocal power removal event). If the remote control device does notreceive a response from the lighting device, the remote control devicemay determine that the lighting device is unpowered (e.g., a systempower removal event). Also, or alternatively, the remote control devicemay transmit one or more queries to determine if the lighting device isflagged as unpowered.

When the remote control device determines that the power removal eventis a system power removal event, the remote control device may performstate correction (e.g., setting the lighting device to its state priorto the power removal event). The remote control may transmit a query todetermine a previous state of the lighting device. The query may betransmitted to the lighting device. After receiving a response to thequery, the remote control device may transmit a command to the lightingdevice to set the lighting device to the previous state.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an example environment including load control devices.

FIGS. 2A-2D are perspective views of example environments for adjustingand/or retaining state information of control devices.

FIGS. 3-5 are simplified flowcharts of example methods for adjustingand/or retaining state information of control devices.

FIG. 6 is a simplified flowchart of an example method for detecting andflagging power removal events.

FIGS. 7 and 8 are simplified flowcharts of example methods forperforming state correction after power removal events.

FIG. 9 is a block diagram of an example load control device.

FIG. 10 is a block diagram of an example input device.

FIG. 11 is a block diagram of an example network device.

FIG. 12 is a block diagram of an example hub device.

DETAILED DESCRIPTION

FIG. 2A is a diagram of an example load control system 200 (e.g., alighting control system) in which one or more lighting devices, such aswirelessly-controllable light bulbs 212, 222 (e.g., lighting loads) maybe deployed. The load control system 200 may comprise a wall-mountedload control device 210 (e.g., a mechanical switch, such as, a toggleswitch, a paddle switch, a pushbutton switch, a “light switch,” or othersuitable switch), which may be coupled in series electrical connectionbetween an alternating-current (AC) power source 202 and the first lightbulb 212. In one example, the lighting devices or light bulbs 212, 222may include both a lighting load (e.g., a light-emitting diode (LED)light source) and a load control device, such as a lighting controldevice (e.g., may include an internal load control circuit, such as anLED drive circuit). In another example, the lighting devices or lightbulbs 212, 222 may include a lighting load, which may be controlled byan external load control device.

The light bulb 212 may be installed in a ceiling-mounted downlightfixture 214. In addition, the light bulb 212 may be installed in awall-mounted lighting fixture or other lighting fixture mounted toanother surface. The wall-mounted load control device 210 may include aninternal switching mechanism for controlling the power delivered to thelight bulb 212. In response to actuations of an actuator (e.g., a toggleactuator 216), the wall-mounted load control device 210 may beconfigured to close and open the switching mechanism to turn the lightbulb 212 on and off, respectively. Because the wall-mounted load controldevice 210 may be configured to turn the light bulb 212 on and off(e.g., the light bulb 212 is downstream of the wall-mounted load controldevice 210), the light bulb 212 may be considered to be a switchedelectrical device. The wall-mounted load control device 210 may beadapted to be wall-mounted in a standard electrical wallbox.

The second light bulb 222 may be installed in a lamp (e.g., a table lamp224). The table lamp 224 may be plugged (e.g., via an electrical plug220) into an electrical receptacle 226 that is powered by the AC powersource 202. The light bulb 222 may be installed in the table lamp 224 orother lamp that may be plugged into the electrical receptacle 226. Thetable lamp 224 may comprise an internal switching mechanism (not shown)coupled in series between the AC power source 202 and the light bulb222. The table lamp 224 may also include an actuator 225 for controllingthe internal switching mechanism to control the power delivered to thelight bulb 222. In response to actuations of the actuator 225 of thetable lamp 224, the internal switching mechanism of the table lamp 224may be configured to turn the light bulb 222 on and off. Because theinternal switching mechanism of the table lamp 224 may be configured toturn the light bulb 222 on and off (e.g., the light bulb 222 isdownstream of the internal switching mechanism of the table lamp 224),the light bulb 222 may be considered to be a switched electrical device.

The load control system 200 may include one or more input devices, e.g.,radio-frequency (RF) transmitters, such as a battery-powered handheldremote control device 250. The light bulb 212 and/or the light bulb 222may be configured to receive digital messages via wireless signals,e.g., radio-frequency (RF) signals 206 (e.g., ZIGBEE®; NFC; BLUETOOTH®;WI-FI®; or a proprietary communication channel, such as CLEAR CONNECT™,etc.). The wireless signals may be transmitted by the battery-poweredremote control device 250. In response to the received digital messages,the respective light bulbs 212, 222 may be turned on and off (e.g., astate change event), and/or the intensities of the respective lightbulbs 212, 222 may be increased or decreased. The battery-powered remotecontrol device 250 may include one or more actuators 252 (e.g., one ormore of an on button, an off button, a raise button, a lower button, ora preset button). The battery-powered remote control device 250 maytransmit the RF signals 206 in response to actuations of one or more ofthe actuators 252. The battery-powered remote control device 250 may behandheld. The battery-powered remote control device 250 may be mountedvertically to a wall, or supported on a pedestal to be mounted on atabletop. Examples of battery-powered remote control devices aredescribed in greater detail in commonly-assigned U.S. Pat. No.8,330,638, issued Dec. 11, 2012, entitled WIRELESS BATTERY-POWEREDREMOTE CONTROL HAVING MULTIPLE MOUNTING MEANS, and U.S. PatentApplication Publication No. 2012/0286940, published Nov. 15, 2012,entitled CONTROL DEVICE HAVING A NIGHTLIGHT, the entire disclosures ofwhich are hereby incorporated by reference.

Digital messages transmitted by the input devices (e.g., thebattery-powered remote control device 250) may include a command and/oridentifying information, such as a serial number (e.g., a uniqueidentifier) associated with the transmitting input device. Each of theinput devices may be associated with (e.g., assigned to) the light bulb212 and/or the light bulb 222 during a configuration procedure of theload control system 200, such that the light bulb 212 and/or the lightbulb 222 may be responsive to digital messages transmitted by the inputdevices via the RF signals 206. Examples of associating wireless controldevices during a configuration procedure are described in greater detailin commonly-assigned U.S. Patent Application Publication No.2008/0111491, published May 15, 2008, entitled RADIO-FREQUENCY LIGHTINGCONTROL SYSTEM, and U.S. Patent Application Publication No.2013/0214609, published Aug. 22, 2013, entitled TWO-PART LOAD CONTROLSYSTEM MOUNTABLE TO A SINGLE ELECTRICAL WALLBOX, the entire disclosuresof which are hereby incorporated by reference.

The load control system 200 may include a hub device 280 configured toenable communication with a network 282, e.g., a wireless or wired localarea network (LAN). The hub device 280 may be connected to a router viaa wired digital communication link 284 (e.g., an Ethernet communicationlink). The router may allow for communication with the network 282,e.g., for access to the Internet. The hub device 280 may be wirelesslyconnected to the network 282, e.g., using wireless technology, such asWi-Fi technology, cellular technology, etc. The hub device 280 may beconfigured to transmit communication signals (e.g., RF signals 206) tothe light bulb 212 and/or the light bulb 222 for controlling therespective light bulbs in response to digital messages received fromexternal devices via the network 282. The hub device 280 may communicatevia one or more types of RF communication signals (e.g., ZIGBEE®; NFC;BLUETOOTH®; WI-FI®; cellular; a proprietary communication channel, suchas CLEAR CONNECT™, etc.). The hub device 280 may be configured toreceive RF signals 206 from the battery-powered remote control device250, the light bulb 212, and/or the light bulb 222 (e.g., using ZIGBEE®;NFC; BLUETOOTH®; or a proprietary communication channel, such as CLEARCONNECT™, etc.). The hub device 280 may be configured to transmitdigital messages via the network 282 for providing data (e.g., statusinformation) to external devices.

The hub device 280 may operate as a central controller for the loadcontrol system 200, and/or relay digital messages between the controldevices (e.g., lighting devices) of the load control system and thenetwork 282. The hub device 280 may be plugged (e.g., via electricalplug 228) into an electrical receptacle 229 that is powered by the ACpower source 202. The hub device 280 may receive power without beingcontrolled by the same actuator as the light bulbs 212, 222 (e.g.,without being controlled by the toggle actuator 216). For example,toggle actuator 216 may not turn the hub device 280 on and off. The hubdevice 280 may receive power from an external power source. For example,the hub device 280 may receive power from a battery. The hub device 280may be on-site at the load control system 200 or at a remote location.Though the hub device 280 is shown as a single device, the load controlsystem 200 may include multiple hub devices and/or the functionalitythereof may be distributed across multiple devices.

The load control system 200 may include a network device 290, such as, asmart phone (for example, an iPhone® smart phone, an Android® smartphone, or a Blackberry® smart phone), a personal computer, a laptop, awireless-capable media device (e.g., MP3 player, gaming device, ortelevision), a tablet device, (for example, an iPad® hand-held computingdevice), a Wi-Fi or wireless-communication-capable television, or anyother suitable network communication or Internet-Protocol-enableddevice. The network device 290 may be operable to transmit digitalmessages in one or more Internet Protocol packets to the hub device 280via RF signals 208 either directly or via the network 282. For example,the network device 290 may transmit the RF signals 208 to the hub device280 via a Wi-Fi communication link, a Wi-MAX communications link, aBluetooth® communications link, a near field communication (NFC) link, acellular communications link, a television white space (TVWS)communication link, or any combination thereof. The RF signals 208 maybe communicated using a different protocol and/or wireless band than theRF signals 206. For example, the RF signals 208 may be configured forWi-Fi communication or cellular communication, while RF signals 206 maybe configured for ZIGBEE® or a proprietary communication channel, suchas CLEAR CONNECT™. In another example, the RF signals 208 and the RFsignals 206 may be the same. Examples of load control systems operableto communicate with network devices on a network are described ingreater detail in commonly-assigned U.S. Patent Application PublicationNo. 2013/0030589, published Jan. 31, 2013, entitled LOAD CONTROL DEVICEHAVING INTERNET CONNECTIVITY, the entire disclosure of which is herebyincorporated by reference.

The network device 290 may include a visual display 292. The visualdisplay 292 may include a touch screen that may include, for example, acapacitive touch pad displaced overtop the visual display, such that thevisual display may display soft buttons that may be actuated by a user.The network device 290 may include a plurality of hard buttons, e.g.,physical buttons (not shown), in addition to the visual display 292. Thenetwork device 290 may download a product control application forallowing a user of the network device 290 to control the load controlsystem 200. In response to actuations of the displayed soft buttonsand/or hard buttons, the network device 290 may transmit digitalmessages to the light bulb 212, the light bulb 222, and/or the hubdevice 280 through the wireless communications described herein.

The network device 290 may transmit digital messages via the RF signals208 for controlling the light bulb 212 and/or the light bulb 222. Thenetwork device 290 may transmit digital messages to the light bulb 212and/or the light bulb 222 via the hub device 280 (e.g., using ZIGBEE®;NFC; BLUETOOTH®; or a proprietary communication channel, such as CLEARCONNECT™, etc.). For example, the network device 290 may transmitdigital messages to turn the light bulbs 212, 222 on, off, and/or modifythe intensities of respective light bulbs 212, 222. The network device290 may vary the intensity of the light bulbs 212, 222 by varying theamount of power delivered to the light bulbs 212, 222. For example, thenetwork device 290 may increase or decrease the intensity of the lightbulbs 212, 222 from a minimum intensity (e.g., approximately 1%) to amaximum intensity (e.g., approximately 100%). The light bulb 212 and/orthe light bulb 222 may communicate with the hub device via RF signals206 (e.g., to transmit status information). For example, the light bulb212 and/or the light bulb 222 may be configured to communicate with thehub device 280 (e.g., using ZIGBEE®; NFC; BLUETOOTH®; or a proprietarycommunication channel, such as CLEAR CONNECT™, etc.) in response todigital messages received from the battery-powered remote control device250 and/or another cause of change in lighting intensity. The hub device280 may be configured to transmit RF signals 208 to the network device290. For example, the RF signals 208 transmitted to the network device290 may be used for displaying data (e.g., status information) on thevisual display 292 of the network device 290.

The operation of the load control system 200 may be programmed andconfigured using the hub device 280 and/or the network device 290. Anexample of a configuration procedure for a wireless load control systemis described in greater detail in commonly-assigned U.S. PatentApplication Publication No. 2014/0265568, published Sep. 18, 2014,entitled COMMISSIONING LOAD CONTROL SYSTEMS, the entire disclosure ofwhich is hereby incorporated by reference.

The lighting devices (e.g., the light bulb 212, the light bulb 222) mayinclude an ability to store information. For example, the light bulb 212and/or the light bulb 222 may include memory. The memory may be volatileand/or non-volatile memory. The memory may be used for saving one ormore states (e.g., power states) of the lighting devices. For example,the light bulb 212 and/or the light bulb 222 may have an on power stateand/or an off power state. The on power state of the light bulb 212and/or the light bulb 222 may be characterized by an intensity state, acolor (e.g., a color temperate) state, etc. The intensity state of thelight bulb 212 and/or the light bulb 222 may be the intensity level(e.g., 10%, 50%, 80%) of the light bulb 212 and/or the light bulb 222.The light bulbs 212, 222 may be configured to store their respectivestates in memory. Also, or alternatively, the light bulbs 212, 222 maybe configured to store states of other devices in their respectivememory. The light bulbs 212, 222 may store one or more power states forretention at a later time.

If the hub device 280 is included in the load control system 200, thehub device 280 may store information. For example, the hub device 280may include memory that may be volatile and/or non-volatile memory. Thememory may be used for saving one or more states (e.g., power states) ofthe lighting devices and/or one or more states of the hub device 280.For example, the hub device 280 may have a powered state when receivingpower and an unpowered state when insufficient power is being received.The hub device 280 may store the power states of the lighting devicesand/or the power states of the hub device 280. The hub device 280 maystore the intensity states and/or color states of the lighting devices.The hub device 280 may store the power states of lighting devices forretention at a later time.

The hub device 280 may be used to set a state (e.g., power state) of oneor more of the lighting devices of the load control system 200 (e.g.,the light bulb 212, the light bulb 222). For example, the hub device 280may be used to set the state of one or more of the lighting devices toan on power state, an off power state, a defined intensity state (e.g.,a preset intensity state), a defined color state, etc. The lightingdevices may be in the on power state to be controlled to other states,such as the defined intensity state or the defined color state, forexample. The lighting devices may change their respective states to bealigned with the states provided by the hub device 280 (e.g., a statechange event). The hub device 280 may change the states of the lightingdevices to be aligned with the states stored by the hub device 280 whenelectrical power is being provided to the lighting devices. For example,the hub device 280 may set a state of the light bulb 212 to an on powerstate. If power is being provided to the light bulb 212 (e.g., thetoggle actuator 216 is turned to the on position), the light bulb 212may be turned to the on power state. If electrical power is not providedto the lighting load (e.g., a power removal event occurs, such as thetoggle actuator 216 is turned to the off position), the hub device 280may not be able to set the light bulb 212 to the on power state and/orto a defined intensity or color. For example, the hub device 280 may beprecluded from setting the state of the light bulb 212 to the on powerstate or to a defined intensity or color if insufficient electricalpower is being provided to the light bulb 212 (e.g., a power removalevent occurs, such as the toggle actuator 216 is turned to the offposition). The hub device 280 may set a state of the light bulb 212 tothe off power state. For example, if power is being provided to thelight bulb 212 (e.g., the toggle actuator 216 is turned to the onposition), the hub device 280 may set the power state of the light bulb212 to the off power state, based on the information stored by the hubdevice 280. The network device 290 may be used to set a state (e.g.,power state), or not set a state, of one or more lighting devices in amanner similar to the hub device 280.

The hub device 280 and/or the network device 290 may set a state (e.g.,a power state) of one or more lighting devices by sending a digitalmessage to the light bulbs 112, 122 (e.g., a state change event). Thehub device 280 and/or the network device 290 may send the digitalmessages directly to the light bulbs 112, 122. The hub device 280 and/orthe network device 290 may send the digital messages to the light bulbs112, 122 via an intermediary device (e.g., via a separate hub device,network device, and/or control device). The digital message may includethe power state to which the lighting devices may be set. The lightbulbs 112, 122 may set the respective lighting devices to the receivedpower state. The light bulbs 112, 122 may store the received powerstate. The light bulbs 112, 122 may transmit a digital message to thehub device 280 and/or the network device 290. For example, the lightbulbs 112, 122 may transmit a digital message to the hub device 280and/or the network device 290 as an acknowledgement that the light bulbs112, 122 have received and/or stored the power state sent by the hubdevice 280 and/or the network device 290.

The hub device 280 may monitor when the remote control device 250changes the power state of the lighting devices and update the powerstates that are stored in memory. The hub device 280 may identifydigital messages from the remote control device 250 that are transmittedto control the power state of the lighting devices. In response to thehub device 280 identifying a command to change the power state in thedigital messages transmitted from the remote control device 250, the hubdevice 280 may update the power states stored in memory. The hub device280 may await a confirmation of the change in power state from thelighting devices before updating the stored power state.

A power state as set by the hub device 280 and/or the network device 290may be different than the actual state of the lighting devices (e.g.,light bulb 212). As described herein, the hub device 280 and/or thenetwork device 290 may be configured to set a power state of thelighting devices (e.g., the light bulb 212). For example, the hub device280 and/or the network device 290 may set a power state of the lightbulb 212 to an on power state. As long as electrical power is providedto the lighting devices, the lighting devices may set their respectivepower states to the power states provided by the hub device 280 and/orthe network device 290. The power states (e.g., on power states) may beoverridden by a power removal event during which the actual states ofthe lighting devices may be different than the power states stored bythe hub device 280 and/or the network device 290. For example, if poweris removed from the lighting load via a power removal event, the lightbulb 212 may be in an off power state. A power removal event may includea user turning the toggle actuator 216 to the off position. For example,if a user turns the toggle actuator 216 to the off position, the lightbulb 212 may be turned to an off power state, even if the hub device280, the network device 290, and/or the remote control device 250 hasset the power state of the light bulb 212 to the on power state.

A power removal event may also include a power outage (e.g., a blackoutand/or a brownout). For example, power may be removed from the lightingdevices if one or more portions (e.g., rooms) of a load control system200 experiences a blackout, brownout, etc. If power is removed from thelight bulb 212 (e.g., via a power removal event, such as a blackout),the light bulb 212 may be turned to an off power state, notwithstandingthat the hub device 280, the network device 290, and/or remote controldevice 250 has set the power state of the light bulb 212 to be an onpower state.

The prior power states (e.g., the power states of lighting devices setprior to a power removal event) may be stored by the light bulb 212, thelight bulb 222, the hub device 280, the network device 290, and/orstored in an external database (e.g., cloud database) via the network282. The prior power states of lighting devices may be recalled at apredefined time. The prior power states of the lighting devices may berecalled after a predetermined event (e.g., upon a user action).

A power removal event may be a local power removal event or a systempower removal event. A local power removal event may occur as a resultof a user controlling the toggle actuator 216 and/or the actuator 225 toan off position. For example, a user may actuate the toggle actuator 216and/or the actuator 225 in an attempt to turn off the power and/orfunctionality of the respective light bulbs 212, 222. A single controldevice or multiple control devices located within a location (e.g., oneor more control devices located within a room or controlled by the sameswitch) may experience a local power removal event. A system powerremoval event may be a blackout, brownout, or other power removal eventthat affects the devices in the load control system 200. The hub device280 may be able to determine whether a power removal event is a systempower removal event (e.g., a blackout, brownout, etc.). A system powerremoval event may involve the removal of power to the hub device 280 andone or more control devices within the load control system 200. Inresponse to the system power removal event, the hub device 280 mayoperate in an unpowered state (e.g., powered off). The hub device 280may enter a battery powered mode after detecting the loss of power, ormay remain off until the return of power from the AC circuit. The hubdevice 280 may detect a return to the powered state and may subsequentlycontrol the light bulbs 212, 222 to a prior power state (e.g., prior tothe loss of power). The light bulbs 212, 222 may also, or alternatively,store their prior power states locally and recall the prior power statesafter a system power removal event is detected (e.g., via an indicationfrom the hub device 280).

After the lighting devices (e.g., light bulbs 212, 222) and/or the hubdevice 280 determines that the power removal event is a local powerremoval event at one of the lighting devices (e.g., the user turning offpower to an AC circuit), the lighting devices and/or the hub device 280may refrain from transmitting a prior power state. After a local powerremoval event has ended and power is returned to the lighting devicesaffected by the local power removal event (e.g., the user turning on thepower to the AC circuit), lighting devices affected by the local powerremoval event may turn on to a default intensity level (e.g., maximumintensity level, a defined intensity level, such as eighty-five percent,etc.) or to a prior intensity level. The hub device 280 and/or otherlighting devices may refrain from transmitting messages to detectwhether a power removal event has occurred and/or from controlling thepower state of the affected lighting devices. For example, after thelight bulb 222 and/or the hub device 280 determines that a power removalevent to the light bulb 212 was a local power removal event (e.g.,because toggle actuator 216 was actuated to the off position), the lightbulb 222 and/or the hub device 280 may refrain from transmitting adigital message to control the power state of the light bulb 212.

After the lighting devices and/or the hub device 280 determines that thepower removal event is a system power removal event (e.g., a brownout,blackout, etc.), the lighting devices and/or the hub device 280 maymodify the power states of the lighting devices to the prior powerstates of the lighting devices. For example, upon the light bulbs 212,222 and/or the hub device 280 determining that the power removal eventto the light bulbs 212, 222 is a system power removal event (e.g., bydetermining that the light bulb 212 and the light bulb 222 haveexperienced a power removal event), the light bulbs 212, 222 and/or thehub device 280 may set the power state of the lighting devices to therespective prior power states. Thus, in the event of a system powerremoval event, the light bulbs 212, 222 may be prevented from operatingat an undesirable default intensity level (e.g., maximum intensitylevel, a defined intensity level, such as eighty-five percent, etc.)when power is returned to the light bulbs 212, 222, and may even remainin an off power state when that is the prior power state of the lightbulbs 212, 222 before the system power removal event.

In an example, the light bulb 212 may be in the off power state (e.g.,zero percent intensity level), but still receiving power from the ACpower source 202. If the light bulb 212 experiences a local powerremoval event, and power is returned to the light bulb 212, the lightbulb 212 may turn on to a default intensity level, such as a maximumintensity level or a defined intensity level, e.g., eighty-five percent.If the light bulb 212 experiences a system power removal event, and thehub device 280 is implemented in the system 200, the hub device 280 maydetect the system power removal event and send a digital message thatoverrides the default intensity level of the light bulb 212 with thestored prior power state (e.g., zero percent intensity level) of thelight bulb 212 before the system power removal event. If the light bulb212 stores the prior power state (e.g., zero percent intensity level) ofthe light bulb 212 locally and detects that a system power removal eventhas occurred, the light bulb 212 may override the default power statewith the prior power state of the light bulb 212 before the system powerremoval event and remain in the off power state (e.g., zero percentintensity level). In the examples provided, the light bulb 212 mayremain off, or return to another prior power state, in the event of asystem power removal event.

The lighting load of the light bulb 212 may operate at the recalledprior power state at a predefined time and/or the lighting load of thelight bulb 212 may function according to the recalled prior power stateafter a predefined duration (e.g., five minutes after the power isreturned to the lighting load and/or immediately after the power isreturned to the lighting load). For example, upon a system power removalevent beginning and ending, the light bulb 212 may recall (e.g., frommemory) that the prior power state of the lighting load was an on powerstate at an intensity state of eighty percent. Upon the power removalevent ending, the light bulb 212 may operate the lighting load in the onpower state at the intensity state of eighty percent. The lighting loadmay function at eighty percent in the morning, and/or the lighting loadmay function at the defined intensity upon a predefined duration (e.g.,ten minutes, immediately, etc.) after the power removal event ends.

Other devices (e.g., the hub device 280 and/or the network device 290)within the load control system 200 may be used to coordinate the storageand/or retrieval of power states of lighting devices. The hub device 280and/or the network device 290 may be used to store power states oflighting devices prior to a power removal event (e.g., as the priorpower states). The hub device 280 and/or the network device 290 maycoordinate sending messages, such as messages including power states,among lighting devices. A button (e.g., a “soft” button) on the networkdevice 290 may be actuated to set lighting devices to predefined powerstates. For example, a button on the network device 290 may be actuatedto set the light bulb 212 to a power state of forty percent intensitylevel. Upon the conclusion of a power removal event, the light bulb 212may be set to the power state set by the network device 290 (e.g., anintensity level of forty percent). The light bulb 212 may retrieve theintensity level of forty percent internally (e.g., from memory withinthe light bulb 212) and/or the light bulb 212 may retrieve the intensitylevel of forty percent externally (e.g., from the hub device 280, thenetwork device 290 and/or one or more other lighting devices).

The prior power state may be pushed to the light bulb light bulbs 212,222 after the identification of the end of the power removal eventwithout the light bulbs 212, 222 sending a request. For example, the hubdevice 280 and/or the network device 290 may send a digital message tothe light bulb 212 that indicates a prior power state to which the lightbulbs 212, 222 may each be controlled after the hub device 280 and/orthe network device 290 detect the end of a power removal event (e.g., bydetecting a change from a powered state to an unpowered state, and backto a powered state).

The hub device 280 and/or the network device 290 may detect theoccurrence of a power removal event (e.g., by detecting a change from apowered state to an unpowered state, and back to a powered state) andquery the light bulbs 212, 222 to determine whether the light bulbs 212,222 also experienced the power removal event. The query may include atime or timeframe within which the power removal event was detected atthe hub device 280 and/or the network device 290. The time may be a timeat which the power removal event began and/or the time at which thepower removal event ended. The query may include a device identifier(e.g., unique identifier) of the devices that are intended to respond tothe query. The light bulbs 212, 222 may acknowledge whether a powerremoval event was experienced by transmitting an acknowledgement messageto the hub device 280 when the light bulbs 212, 222 experienced thepower removal event. The acknowledgement message may include the timeand/or timeframe in which the power removal event was detected at therespective light bulbs 212, 222, such that the hub device 280 and/or thenetwork device 290 may determine whether the power removal eventscoincide between the devices. The hub device 280 and/or the networkdevice 290 may determine that the power removal event is a system powerremoval event when the queried light bulbs 212, 222 also experienced thepower removal event and send the prior power state to the light bulbs212, 222. The hub device 280 and/or the network device 290 may send toand/or query the light bulbs 212, 222 periodically, at a time of day,and/or aperiodically (e.g., based on a user action).

The light bulbs 212, 222 may transmit a digital message to the hubdevice 280 that indicates the occurrence of a power removal eventwithout being requested. The digital messages sent from the light bulbs212, 222 may indicate the power states of the light bulbs 212, 222. Thedigital messages may indicate whether a power removal event has occurredto one or more other lighting devices. The digital message may identifythe lighting devices by a name, a number (e.g., unique identifier), etc.The light bulbs 212, 222 may send to and/or query the hub device 280and/or the network device 290 periodically, at a time of day, and/oraperiodically (e.g., based on a user action).

The light bulbs 212, 222 may query for a prior power state afterdetection of a power removal event. For example, the hub device 280and/or the network device 290 may send a digital message to the lightbulb 212 in response to a request for a prior power state by the lightbulbs 212, 222 after the occurrence of a power removal event. The lightbulbs 212, 222 may send a digital message that indicates that a powerremoval event occurred, which may be interpreted by the hub device 280and/or the network device 290 as a request for a prior power state. Thedigital message may include a time or timeframe associated with thepower removal event. If the hub device 280 and/or the network device 290did not experience the power removal event (e.g., within a coincidingtime period), the hub device 280 and/or the network device 290 mayprevent the sending of the prior power state.

The light bulbs 212, 222 may send a message to the other devices in thesystem 200. For example, the light bulb 212 may send a message to theother devices that the light bulb 212 experienced a power removal event,which may indicate that the light bulb 212 has regained power after thepower removal event, and the other devices in the system 200 (e.g., thehub device 280, the network device 290 and/or one or more other lightingdevices) may send a digital message indicating a power state at whichthe light bulb 212 should operate.

Though the messages indicating power states and/or identification ofpower removal events may be described herein as being performed by thehub device 280 and/or the network device 290, such functionality may beimplemented at the remote control device 250, and/or at the controldevices (e.g., lighting devices) themselves. For example, one or morelighting devices, such as the light bulb 212, the light bulb 222, etc.,may be used to store the prior power states, identify the occurrence ofa power removal event (e.g., locally and/or by querying other devices),and/or communicate the prior power states to one or more other lightingdevices in response to a system power removal event. The digitalmessages indicating the power states and/or querying for acknowledgementof a power removal event may be received by lighting devices neighboringthe lighting devices sending the messages and/or within a similarlocation as the lighting devices sending the messages. The lightingdevices receiving the messages may set their power state to the powerstate included in the digital messages, or respond to the requests foracknowledgement of a power removal event when such a power removal eventhas occurred locally.

The lighting devices and/or the hub device 280 may be configuredaccording to one or more locations (e.g., rooms). The lighting devicesand/or the hub device 280 may be configured according to one or moresources of power (e.g., AC power source 202). The lighting devicesand/or the hub device 280 may be configured according to one or more ACcircuits. A lighting devices and/or the hub 280 may be identified by acorresponding location, AC power source, and/or AC circuit. Thelocation, AC power source, and/or AC circuit corresponding to a lightingdevice and/or the hub device 280 may be stored by the lighting devicesand/or the hub device 280.

The lighting devices and/or the hub device 280 may receive power fromone or more AC circuits. For example, the light bulb 212 may receivepower from the AC power source 202. The light bulb 212 may receive powerfrom AC power source 202 via an AC circuit. The toggle actuator 216 maybe actuated so that power is provided to the light bulb 212 or so thatpower is not provided to the light bulb 212. The light bulb 222 and thehub device 280 may receive power from the AC power source 202. The lightbulb 212 may receive power from the AC power source 202 via an ACcircuit that is different than the AC circuit providing power to thelight bulb 212. For example, the light bulb 222 may receive power fromthe electrical receptacle 226 and/or the hub device 280 may receivepower from electrical receptacle 229. The electrical receptacles 226,229 may not be controlled by the actuation of a switch (e.g., the loadcontrol device 210 via actuations of the toggle actuator 216). Thelighting devices and/or the hub device 280 may identify the light bulb212 as being controllable by a switch (e.g., the load control device210). The lighting devices and/or the hub device 280 may identify thelight bulb 222 as not being controllable by a switch (e.g., the loadcontrol device 210).

The lighting devices and/or the hub device 280 may determine whetherpower is provided to one or more lighting devices and/or hub devices.The lighting devices and/or the hub device 280 may determine whetherpower is provided to one or more lighting devices and/or hub devicesaccording to the AC circuits from which the lighting devices and/or thehub device 280 receive electrical power. For example, the lightingdevices and/or the hub device 280 may determine if electrical power isprovided to the light bulb 212. The lighting devices and/or the hubdevice 280 may also, or alternatively, determine if electrical power isprovided to the light bulb 222 and/or the hub device 280. The lightingdevices and/or the hub device 280 may determine the type of powerremoval event (e.g., local power removal event, system power removalevent) by determining if one or more AC circuits have been affected by apower removal event. For example, the hub device 280 may determine thata power removal event is a system power removal event (e.g., a brownoutand/or a blackout) by determining that multiple AC circuits (e.g., ACcircuits providing electrical power to the light bulb 212, the lightbulb 222, and/or the hub device 280) have experienced a power removalevent. The lighting devices and/or the hub device 280 may query devices(e.g., lighting devices, the hub device 280, and/or other controldevices) connected to different AC circuits to determine if the powerremoval event is a system power removal event (e.g., a power removalevent affecting more than one AC circuit, such as a brownout orblackout) and/or whether the power removal event is a local powerremoval event (e.g., a power removal event affecting a single ACcircuit), such as when a user physically turns off the toggle actuator216 that controls the light bulb 212. The lighting devices and/or thehub device 280 may query devices positioned within different locations(e.g., rooms) to determine if a power removal event is a system powerremoval event or a local power removal event.

Setting the power state of the lighting devices to the respective priorpower states may be controlled by the user. For example, a user may setthe power state of the light bulb 212 to fifteen percent (e.g., when theuser is away on vacation). If a system power removal event begins andends, the user may apply a setting that is stored at the hub device 280and/or the lighting device 212 to automatically control the light bulb212 to an intensity level of fifteen percent when power is againprovided to the light bulb 212 (e.g., when the power removal eventends). As another example, a user may set the intensity level of thelight bulb 212 to zero percent (e.g., prior to the user being away orgoing to bed). If a system power removal event occurs while the user isaway or is in bed, the intensity level that was previously set by theuser may be used to control the light bulb 212 to an intensity of zeropercent when power is again provided to the light bulb 212 (e.g., whenthe power removal event ends). The user settings may be stored andapplied similar to the prior power state that is stored and appliedherein. User settings may be given priority over a prior power statethat has been stored after the user settings, or the prior power statemay be given priority over the user settings. Although the controldevices (e.g., lighting devices) may be configured to provide light atan intensity displayed prior to a system power removal event, this maybe disabled by the user. For example, a user may configure the controldevices so that they provide light at a default intensity level (e.g.,100% intensity level, 85% intensity level, etc.) upon a system powerremoval event ending.

The hub device 280 and/or the lighting devices may determine whether apower removal event is a local power removal event or a system powerremoval event using one or more factors. For example, the hub device 280and/or the lighting devices may determine that a power removal event isa local power removal event or a system power removal event based on thenumber of control devices (e.g., lighting devices) that have experienceda power removal event. The hub device 280 and/or the lighting devicesmay set a threshold for the number of devices that experienced the powerremoval event indicating that the power removal event was a system powerremoval event. If each of the lighting devices within a load controlsystem have experienced a power removal event, it may be determined thatthe power removal event was a system power removal event. If one or morelighting devices within a load control system have not experienced apower removal event at the same time, power removal events experiencedby the control devices may be determined to be local power removalevents.

The hub device 280 and/or the lighting devices may determine that apower removal event is a local power removal event or a system powerremoval event based on the type of the control devices that haveexperienced a power removal event. Some control devices may not bedownstream of a switch (e.g., the wall-mounted load control device 210).For example, a dimmer device may not be downstream of a switch and maybe configured to control the power delivered to a lighting device, suchas a dimmable light source. Other devices may be downstream of a switch.The light bulb 212, shown in FIG. 2A, may be an example of a device thatis downstream of a switch.

A weighting factor may be used for determining whether a power removalevent is a local power removal event or a system power removal event.For example, control devices (e.g., lighting devices) not downstream ofa switch may be provided a higher weight than control devices downstreamof a switch, when determining whether a power removal event was a localpower removal event or a system power removal event. For example, adimmer device (such as dimmer device 218, shown in FIG. 2B) experiencinga power removal event may be provide a larger weight than the light bulb212 experiencing a power removal event, when determining whether a powerremoval event was a local power removal event or a system power removalevent. If the light bulb 212 experiences a power removal event and thedimmer device continues receiving power at the time of the power removalevent at the bulb 212, it may be determined that the power removal eventexperienced by the light bulb 212 is a local power removal event. Ifdimmer device experiences a power removal event, the hub device 280and/or the lighting devices may determine that the power removal eventexperienced by the dimmer device is a system power removal event.

The light bulb 212, the light bulb 222, and the hub device 280 may beelectrically coupled to AC power source 202. Although the light bulb212, the light bulb 222, and the hub device 280 are electrically coupledto the same power source (e.g., AC power source 202), the light bulb 212is on a different circuit than the light bulb 222 and the hub device280. The light bulb 212 is electrically coupled to the wall-mounted loadcontrol device 210. The light bulb 222 and the hub device 280 are notelectrically coupled to the wall-mounted load control device 210. Thehub device 280 and/or lighting devices may query more than one controldevice (e.g., the light bulb 212 and the light bulb 222) to determine ifa power removal event is a system power removal event or a local powerremoval event. The hub device 280 and/or lighting devices may query thehub device 280 and one or more control devices to determine if a powerremoval event is a system power removal event or a local power removalevent. For example, the hub device 280 may query the light bulb 212 andthe light bulb 222 to determine if a power removal event is a systempower removal event or a local power removal event. If the light bulb212 experienced a power removal event and the light bulb 222 experienceda power removal event, the hub device 280 may determine that the powerremoval events are system power removal events (e.g., because more thanone control device on more than one AC circuit experienced a powerremoval event). If the light bulb 212 experienced a power removal event,the light bulb 222 experienced a power removal event, and the hub device280 experienced a power removal event, it may further be determined thatthe power removal events are system power removal events. If the lightbulb 212 experienced a power removal event and the light bulb 222 didnot experience a power removal event, the hub device 280 may determinethat the power removal event to the light bulb 212 was a local powerremoval event (e.g., the light bulb 212 experienced a power removalevent when a user turned the toggle actuator 216 to the off position).

The hub device 280 may query control devices and/or hub devices in oneor more locations (e.g., rooms) to determine if a power removal eventwas a system power removal event or a local power removal event. Forexample, if power removal events occurred within more than one room, thehub device 280 may determine that the power removal event was a systempower removal event. The hub device 280 may query, on a periodic basis(e.g., every 10 seconds, 5 minutes, 1 hour, etc.) whether the controldevices have experienced a power removal event. The hub device 280 mayquery, aperiodically (e.g., based on a user actuation at the hub device280), whether the control devices have experienced a power removalevent. Also, or alternatively, the hub device 280 may query controldevices to determine if the control devices have experienced a powerremoval upon the hub device 280 regaining power after experiencing apower removal event.

The control devices (e.g., lighting devices, such as the light bulb 212)may query control devices (e.g., other lighting devices, such as thelight bulb 222) to determine whether the control devices haveexperienced a power removal event. The light bulb 212 may determinewhether the light bulb 212 has experienced a power event. The light bulb212 may determine whether the power removal event of the other controldevice (e.g., the light bulb 222) and/or the power removal event of thelight bulb 212 was a system power removal event or a local power removalevent. For example, the light bulb 212 may query the light bulb 222 todetermine whether the light bulb 222 has experienced a power removalevent. The light bulb 212 may query the light bulb 222 and/or accesslocal storage to determine if the light bulb 222 and/or the light bulb212 has experienced a power removal event.

The hub device 280 and/or control devices (e.g., lighting devices) mayperform a query to determine whether a power removal event occurred,and/or the type of the power removal event, based on one or moreconditions. For example, the lighting devices (e.g., the light bulb 212)may perform a query to determine whether a power removal event occurred,and/or the type of the power removal event, after the light bulb 212loses and regains power. The light bulb 212 may query other lightingdevices after regaining power and/or the light bulb 212 may query thehub device 280 after regaining power. After regaining power, the lightbulb 212 may query other lighting devices and/or the hub device 280 todetermine whether the other lighting devices and/or the hub device 280have experienced, and/or are experiencing, a power removal event.

If the other lighting devices and/or the hub device 280 haveexperienced, and/or are experiencing, a power removal event, the lightbulb 212 may determine whether the power removal event experienced bythe other control devices and/or the hub device 280 occurred at the sametime that the light bulb 212 lost power. The light bulb 212 may performthis determination by requesting the time of the power removal events,the duration of the power removal events, etc. For example, if the othercontrol devices and/or the hub device 280 experienced a power removalevent at the same time, and/or for the same duration that the light bulb212 experienced the power removal event, the power removal event may bedetermined to be a system power removal event. If the other controldevices and/or the hub device 280 did not experience a power removalevent, and/or if the other control devices and/or the hub device 280 didnot experience a power removal event at the same time as the light bulb212, the power removal event may be determined to be a local powerremoval event.

The hub device 280 may perform a query to determine whether a powerremoval event occurred, and/or the type of the power removal event,after the hub device 280 loses and regains power. The hub device 280 mayquery lighting devices after regaining power. The hub device 280 mayquery other hub devices after regaining power. After regaining power,the hub device 280 may query other hub devices and/or lighting devicesto determine whether the other hub devices and/or lighting devices haveexperienced, and/or are experiencing, a power removal event.

If the other hub devices and/or the lighting devices have experienced,and/or are experiencing, a power removal event, the hub device 280 maydetermine whether the power removal event experienced by the other hubdevices and/or the lighting devices occurred at the same time that thehub device 280 lost power. The hub device 280 may perform thisdetermination by requesting the time of the power removal events, theduration of the power removal events, etc. For example, if the other hubdevices and/or the lighting devices experienced a power removal event atthe same time, and/or for the same duration, that the hub device 280experienced the power removal event, the power removal event may bedetermined to be a system power removal event. If the other hub devicesand/or the lighting devices did not experience a power removal event,and/or if the other hub devices and/or the lighting devices did notexperience a power removal event at the same time as the hub device 280,the power removal event may be determined to be a local power removalevent.

The hub device 280 and/or the lighting devices may perform a query todetermine whether a power removal event occurred, and/or the type of thepower removal event, periodically. For example, the hub device 280and/or the lighting devices may perform a query to determine whether apower removal event occurred, and/or the type of the power removal eventat intervals of five minutes, thirty minutes, two hours, etc. The hubdevice 280 and/or the lighting devices may perform a query to determinewhether a power removal event occurred, and/or the type of the powerremoval event, aperiodically. For example, the hub device 280 and/or thelighting devices may perform a query to determine whether a powerremoval event occurred, and/or the type of the power removal event,based on a user action and/or based on a time of day. The hub device 280and/or the lighting devices may perform a query to determine whether apower removal event occurred, and/or the type of the power removalevent, based on one or more of the factors, or a combination of thefactors, described herein.

The hub device 280 and/or the lighting devices may perform a query todetermine whether a power removal event occurred, and/or the type of thepower removal event, based on receiving a message from one or more otherdevices. For example, another control device may send the hub device 280and/or lighting devices a message. The message may request that the hubdevice 280 and/or the lighting devices query other control devicesand/or hub devices to determine whether a power removal event occurred,and/or the type of the power removal event that may have occurred. Theother control devices may send this message to the hub device 280 and/orthe lighting devices for one or more reasons. For example, the othercontrol devices may send this message to the hub device 280 and/or thelighting devices after the control devices regain power (e.g., the othercontrol devices regain power after a power removal event). The othercontrol devices may send this message to the hub device 280 and/or thelighting devices, e.g., periodically or aperiodically.

As described above, the light bulb 212, the light bulb 222, and the hubdevice 280 are coupled to AC power source 202. Although the light bulb212, the light bulb 222, and the hub device 280 are coupled to the samepower source (e.g., AC power source 202), the light bulb 212 is on adifferent circuit than the light bulb 222 and the hub device 280. Thelight bulb 212 is coupled to the wall-mounted load control device 210.The light bulb 222 and the hub device 280 are not coupled to thewall-mounted load control device 210. The light bulb 212 may query oneor more control devices to determine if a power removal event is asystem power removal event or a local power removal event. The lightbulb 212 may query the hub device 280 and one or more control devices todetermine if a power removal event is a system power removal event or alocal power removal event. For example, the light bulb 212 may query thelight bulb 222 to determine if a detected power removal event is asystem power removal event or a local power removal event. If the lightbulb 222 also experienced a power removal event, the light bulb 212 maydetermine that the power removal events are system power removal events(e.g., because more than one control device on more than one AC circuitexperienced a power removal event). If the light bulb 212 experienced apower removal event, the light bulb 222 experienced a power removalevent, and the hub device 280 experienced a power removal event, it mayfurther be determined that the power removal events are system powerremoval events. If the light bulb 212 experienced a power removal eventand the light bulb 222 did not experience a power removal event, thelight bulb 212 may determine that the power removal event to the lightbulb 212 was a local power removal event (e.g., the light bulb 212experienced a power removal event when a user turned the toggle actuator216 to the off position).

The light bulb 212 may query other lighting devices and/or the hubdevices in one or more locations (e.g., rooms) to determine if a powerremoval event was a system power removal event or a local power removalevent. For example, if power removal events occurred within more thanone room, the light bulb 212 may determine that the power removal eventwas a system power removal event. The light bulb 212 may query, on aperiodic basis (e.g., every 10 seconds, 5 minutes, 1 hour, etc.) whetherother lighting devices and/or the hub devices have experienced a powerremoval event. The light bulb 212 may query, aperiodically (e.g., basedon a user action), whether the other lighting devices and/or the hubdevices have experienced a power removal event. Also, or alternatively,the light bulb 212 may query the other lighting devices and/or the hubdevices to determine if the other lighting devices and/or the hubdevices have experienced a power removal upon the light bulb 212regaining power after experiencing a power removal event.

The hub device 280 may comprise an additional source of power (e.g., aninternal or external battery). The battery may provide power to the hubdevice 280 in the event that electrical power from an AC power source(such as AC power source 202, shown in FIG. 2) ceases to provide power.For example, the hub device 280 may receive electrical power from abattery if the hub device 280 experiences a power removal event (e.g., asystem power removal event and/or a local power removal event). The hubdevice 280 may be configured to determine that it is not receiving powerfrom the AC power source, but is being powered from the battery. If thehub device 280 experiences a power removal event and the hub device 280begins receiving power from the battery, the hub device 280 may querycontrol devices (e.g., lighting devices, such as the light bulb 212 andthe light bulb 222) to determine if the power removal event to the hubdevice was a system power removal event or a local power removal event.

For example, after the hub device 280 experiences a power removal eventand receives power from a battery, the hub device 280 may query thelight bulb 212 to determine if light bulb 212 has experienced a powerremoval event. The hub device 280 may query the light bulb 212 todetermine whether the light bulb experienced a power removal event atthe same time as the hub device 280. If the light bulb 212 experienced apower removal event, and/or if the light bulb 212 experienced the powerremoval event at the same time as the hub device, the hub device 280 maydetermine that the power removal event was a system power removal event.If the light bulb 212 did not experience a power removal event, and/orif the light bulb 212 experienced a power removal event at a differenttime than the hub device 280, the hub device 280 may determine that thepower removal event of the hub device was a local power removal event.The hub device may query one or more other control devices (e.g., thelight bulb 222) to determine if the power removal event experienced bythe hub device was a system power removal event or a local power removalevent.

FIG. 2B shows a load control system 200 a having a wall-mounted loadcontrol device (e.g., a dimmer device 218) for controlling the amount ofpower delivered to a lighting device, such as a light bulb 212 a (e.g.,a lighting load). As shown in FIG. 2B, the light bulb 212 a may comprisea standard, dimmable light bulb (e.g., a light bulb that is notresponsive to wireless signals). The dimmer device 218 may be configuredto control the amount of power delivered to the light bulb 212 a using aphase-control dimming technique. The dimmer device 218 may includeactuators, such as buttons 219. The dimmer device 218 may be configuredto control the power delivered to the light bulb 212 a in response toactuation of buttons 219. The dimmer device 218 may be configured toreceive digital messages via wireless signals, e.g., radio-frequency(RF) signals 206 (e.g., ZIGBEE®; NFC; BLUETOOTH®; WI-FI®; or aproprietary communication channel, such as CLEAR CONNECT™, etc.).Examples of wall-mounted dimmer devices are described in greater detailin U.S. Pat. No. 5,248,919, issued Sep. 28, 1993, entitled LIGHTINGCONTROL DEVICE, and U.S. Patent Application Publication No.2014/0132475, published May 15, 2014, entitled WIRELESS LOAD CONTROLDEVICE, the entire disclosures of which are hereby incorporated byreference.

The dimmer device 218 may be configured to control the power deliveredfrom the AC power source 202 to the light bulb 212 a to control theintensity level of the light bulb 212 a. The dimmer device 218 mayretain the power state of the light bulb 212 a. The dimmer device 218may be configured to retain the power state of the light bulb 212 a toan on power state. For example, dimmer device 218 may be configured toretain an intensity level of the light bulb 212 a to a non-zero value(e.g., an intensity level of 1%-100%). The dimmer device 218 may retainthe power state of the light bulb 212 a to an on power state, forexample, by physically maintaining electrical continuity of the circuit(e.g., AC circuit) between AC power source 202 and the light bulb 212 a.The dimmer device 218 may receive the power from the AC power source 202and prevent the power from being sent to the light bulb 212 a to turnthe light bulb 212 a to the off power state. The dimmer device 218 may,however, store a time at which the power is received 202 and/or lostfrom the AC power source 202. The dimmer device 218 may identify when apower outage is a system power outage, as the dimmer device 218 mayreceive power so long as the AC power source 202 is providing power.Because the dimmer device 218 may receive power so long as the AC powersource 202 is providing power (e.g., the dimmer device 218 is notdownstream of a switch, such as wall-mounted load control device 210),the dimmer device 218 may be considered to be an unswitched electricaldevice. The load control system 200 a may also comprise the light bulb212, as shown in FIG. 2A, that receives power from the AC power source202 via the wall-mounted load control device 210 and is responsive tothe RF signals 206.

Referring again to FIG. 2B, as the dimmer device 218 may receive powerfrom the AC power source 202 so long as the AC power source 202 isproviding power, the light bulbs 212 a, 222 and/or the hub device 280may query the dimmer device 218 to determine whether a power removalevent was a local power removal event or a system power removal event.Because the dimmer device 218 may receive power from the AC power source202 so long as the AC power source 202 is providing power, it may bemore reliable for light bulbs 212 a, 222 and/or the hub device 280 toquery the dimmer device 218 to determine the type of power removal eventthan querying other devices (e.g., light bulbs 212 a, 222 and/or hubdevice 280), which may be unplugged from the power source and/or turnedoff by a light switch. The dimmer device 218 may be an indicator thatthe power removal event was a system power removal event. If there aremultiple dimmer devices in the load control system 200, each of thedimmer devices losing power may indicate a system power removal event,while some or none of the dimmer devices losing power may indicate alocal power removal event. The indication of the dimmer devices losingpower may be used in combination to with other devices (e.g., the lightbulbs 212 a, 222, the hub device 280, etc.) to determine whether a powerremoval event was a local power removal event or a system power removalevent.

The dimmer device 218 may not experience a local power removal event.For example, because the dimmer device 218 does not receive power fromthe AC power source 202 through a switch (e.g., the wall-mounted loadcontrol device 210), the dimmer device 218 may not be turned off by auser. A dimmer device 218 may experience a system power removal event.For example, a dimmer device 218 may experience a blackout. Because thedimmer device 218 may not experience a local power removal event, apower removal event experienced by the dimmer device 218 may bedetermined to be a system power removal event. The hub device 280 and/orlighting devices (e.g., the light bulb 212 a and the light bulb 222) maydetermine that the power removal event experienced by the dimmer device218 is a system power removal event.

As another example, the light bulb 222 may experience a power removalevent. The light bulb 222 receives electrical power from electricalreceptacle 226, which is not coupled to dimmer device 218. Because thelight bulb 222 is not coupled to dimmer device 218, the power removalevent to the light bulb 222 may be determined to be a local powerremoval event (e.g., in response to an actuation of the actuator 225 ofthe table lamp 224) and/or the power removal event to the light bulb 222may be determined to be a system power removal event. To determinewhether a power removal event is a local power removal event or a systempower removal event, the power states of one or more lighting devices,dimmer devices, and/or hub devices may be determined. For example, ifthe light bulb 222 is experiencing a power removal event and the dimmerdevice 218 is experiencing a power removal event, it may be determinedthat the power removal event is a system power removal event. If thelight bulb 222 is experiencing a power removal event and the dimmerdevices positioned within one or more rooms are experiencing a powerremoval event, it may be determined that the power removal event is asystem power removal event. If the light bulb 222 is experiencing apower removal event and the dimmer device 218 is not experiencing apower removal event, and vice-versa, it may be determined that the powerremoval event is a local power removal event. The lighting devicesand/or the hub device 280 may determine the power states of one or morelighting devices.

After the lighting devices and/or other devices (e.g., the hub device280) determine that the power removal event is a system power removalevent, the power states of the lighting devices may be adjusted upon thepower removal event ending. For example, upon the power removal eventending, the lighting devices and/or other the hub device 280 may adjustthe power state of the lighting devices to prior power states of thelighting devices (e.g., power states prior to the power removal event).For example, after the lighting devices and/or the hub device 280determine that the power removal event is a system power removal event,the lighting devices and/or the hub device 280 may obtain the priorpower states of the lighting devices (e.g., via memory of the lightingdevices, memory of the hub device 280, memory of the network device 290,memory of an external server, etc.). The lighting devices and/or the hubdevice 280 may send and/or set the power states of the lighting devicesto the obtained prior power states of the lighting devices.

FIG. 2C shows a load control system 200 b having a remote control device270 that may be mounted over a toggle actuator of the wall-mounted loadcontrol device 210 (e.g., such as the toggle actuator 216 shown in FIG.2A). The lighting devices (e.g., the light bulbs 212, 222) may be turnedon or off, or adjust the intensity level, in response to digitalmessages transmitted by the remote control device 270 via the RF signals206 (e.g., state change events). For example, the light bulbs 212, 222may be turned on or off by rotating (e.g., turning) a rotation portionof the remote control device 270, or pressing an actuation portion ofthe remote control device 270. The intensity levels of the light bulbs212, 222 may be increased or decreased by rotating the rotation portionof the remote control device 270 in one direction or another,respectively.

The remote control device 270 may be a retrofit remote control devicecapable of being mounted over the toggle actuator 216 of thewall-mounted load control device 210. The remote control device 270 maybe coupled to the toggle actuator 216 to retain a power state of thelighting devices controlled by the wall-mounted load control device 210.For example, the remote control device 270 may be configured to maintainthe switch installed on the wall-mounted load control device 210 in the“on” position (e.g., by covering the switch when in the “on” position)to maintain the flow of power from the AC power source 202 to thelighting bulb 212. Because the remote control device 270 may beconfigured to maintain the switch installed on the wall-mounted loadcontrol device 210 in the “on” position (e.g., the light bulb 212 is notdownstream of a switch that is able to be controlled to an “off”position), the light bulb 212 downstream of the wall-mounted loadcontrol device 210 with the remote control device 270 mounted theretomay be considered to be an unswitched electrical device. The remotecontrol device 270 may be configured to attach to the toggle actuator216 and hold toggle actuator 216 in the “on” position. Because thetoggle actuator 216 is maintained in an “on” position, the light bulb212 may be held in an on power state.

The remote control device 270 may communicate with other devices (e.g.,the light bulbs 212, 222, the network device 290, and/or the hub device280) to transition the power states of light bulbs 212, 222 (e.g., statechange events). For example, the remote control device 270 maycommunicate digital messages via the RF signals 206 with the light bulbs212, 222 and/or the hub device 280 to transition the power states of thelight bulbs 212, 222. The remote control device 270 may transmit digitalmessages including a move-to-level command that identifies a lightinglevel to which the lighting devices may change. The move-to-levelcommand may indicate an “on” event or an “off” event to turn the lightbulbs 212, 222 on or off, respectively. For example, the “on” event maybe indicated with a 100% lighting level, or another defined lightinglevel. The “off” event may be indicated with a 0% dimming level. Thelighting level for the “on” event and/or the “off” event may also, oralternatively, be stored at the light bulbs 212, 222 and the light bulbs212, 222 may change to the lighting level upon receiving an indicationof the occurrence of the “on” event or “off” event from the remotecontrol device 270. The digital messages may indicate an “on” event whenthe remote control device 270 is rotated a predefined distance in onedirection. The digital messages may indicate an “off” event when theremote control device 270 is rotated a predefined distance in theopposite direction. The digital messages may indicate an “on” event oran “off” event when the remote control device 270 is pressed (e.g., whena button on the face of the remote control device is pressed or theremote control device 270 is pressed in).

The remote control device 270 may transmit digital messages configuredto increase the lighting level of the light bulbs 212, 222 when theremote control device 270 is rotated in one direction. The remotecontrol device 270 may transmit digital messages configured to decreasethe lighting level of the light bulbs 212, 222 when the remote controldevice 270 is rotated in the opposite direction. The digital messagesmay include a move-with-rate command, which may cause the light bulbs212, 222 to change their respective intensity level by a predefinedamount. The move-with-rate command may cause the light bulbs 212, 222 toretain their proportional intensity levels, and/or difference inrespective intensity levels. The remote control device 270 may senddigital messages to increase or decrease the lighting level by apredefined amount when rotated a predefined distance. The amount of theincrease or decrease may be indicated in the digital messages or may bepredefined at the light bulbs 212, 222.

The lighting devices (e.g., the light bulbs 212, 222) and/or the hubdevice 280 may be associated with the remote control device 270. Theunique identifier (e.g., the serial number) of the remote control device270 may be stored at the associated devices for recognizing digitalmessages therefrom for operating according to instructions in thedigital messages.

A lighting device associated with a remote control device that isconfigured to be mounted overtop of an actuator of a light switch (e.g.,the remote control device 270 that is mounted over the toggle actuator216 of the wall-mounted load control device 210) may be assumed to beincapable of experiencing a local power removal event. For example, thelight bulb 212 may be associated with the remote control device 270 forperforming load control. The lighting bulb 212 may be assumed to beincapable of experiencing a local power removal event since the remotecontrol device 270 retains the power state of the light bulb 212 in anon power state. Even when the remote control device 270 is actuated tochange the light bulb 212 to the off power state, power may still beprovided from the AC power source 202 to the light bulb 212 through thewall-mounted load control device 210, which is maintained in the onposition.

The light bulb 212 that is receiving power from the AC power source 202through the wall-mounted load control device 210 having the remotecontrol device 270 may experience a system power removal event. Forexample, the light bulb 212 may experience a blackout. As the remotecontrol device 270 may prevent the light bulb 212 from experiencing alocal power removal event, a power removal event experienced by thelight bulb 212 coupled to the remote control device 270 may bedetermined to be a system power removal event. The light bulb 212 maydetermine that the power removal event experienced by the light bulb 212is a system power removal event since the light bulb 212 is associatedwith the remote control device 270. The hub device 280 may store theassociation of the light bulb 212 with the remote control device 270 andmay determine that the power removal event experienced by the light bulb212 is a system power removal event since the light bulb 212 isassociated with the remote control device 270. The light bulb 212 and/orthe hub device 280 may control the state of the light bulb 212 based onthe determination.

Before being associated with a remote control device (e.g., thebattery-powered remote control device 250 and/or the remote controldevice 270), the light bulb 212 may be configured to operate in anoperation mode. The operation mode may be a switched mode (e.g., havestored in memory that the light bulb 212 should operate in the switchedmode). When operating in the switched mode, the light bulb 212 mayassume that each power removal event is a local power removal event andrely on the hub device 280 and/or other lighting devices to determine ifthe power removal event was a system power removal event. If the lightbulb 212 is associated with the battery-powered remote control device250 (e.g., that is not configured to be mounted over the toggle actuator216 of the wall-mounted load control device 210), the light bulb 212 maybe configured to continue operating in the switched mode. If the lightbulb 212 is associated with at least one remote control device that isconfigured to be mounted over the toggle actuator 216 of thewall-mounted load control device 210 (e.g., the remote control device270), the light bulb 212 may be configured to assume that the light bulb212 is coupled downstream of a switch that is not able to be controlledto the off position. The unique identifier and/or a device typeidentifier of the battery-powered remote control device 250 and/or theremote control device 270 may be stored in memory to indicate theoperation mode. The operation mode may be explicitly indicated in memorybased on the association with the battery-powered remote control device250 and/or the remote control device 270. The light bulb 212 may storein memory that the light bulb 212 should operate in another operationmode, such as an unswitched mode, during which the light bulb 212 mayassume that each power removal event is a system power removal event.

The light bulb 222 may experience a power removal event. The light bulb222 may receive electrical power from the electrical receptacle 226and/or the light bulb 222 may be controlled by another switch or from anAC power source other than the light bulb 212. The light bulb 222 may beunassociated with the remote control device 270. As the light bulb 222is unassociated with remote control device 270, the power removal eventto the light bulb 222 may be determined to be a local power removalevent (e.g., in response to an actuation of the actuator 225 of thetable lamp 224) or a system power removal event. To determine whether apower removal event is a local power removal event or a system powerremoval event, the power states of one or more lighting devices and/orthe hub device 280 may be determined. For example, if the light bulb 222is experiencing a power removal event and light bulb 212 is experiencinga power removal event, it may be determined that the power removal eventis a system power removal event. The light bulb 222 may receive anindication from the light bulb 212 that the light bulb 212 is in anunswitched mode or associated with the remote control device 280 and usethis indication to determine that the power removal event that was alsoexperienced by the light bulb 212 was a system power removal event. Ifthe light bulb 222 is experiencing a power removal event and lightingdevices positioned within other rooms are experiencing a power removalevent, it may be determined that the power removal event is a systempower removal event. If the light bulb 222 is experiencing a powerremoval event and light bulb 212 is not experiencing a power removalevent, it may be determined that the power removal event is a localpower removal event.

Upon the lighting devices and/or the hub device 280 determining that thepower removal event is a system power removal event, the power state ofthe lighting devices may be adjusted after the power removal event hasended. For example, after the power removal event has ended, thelighting devices and/or the hub device 280 may adjust the power state ofthe lighting devices to the prior power states of the lighting devices.For example, upon the lighting devices and/or the hub device 280determining that the power removal event is a system power removalevent, the lighting devices and/or the hub device 280 may obtain theprior power states of the lighting devices (e.g., via the memory of thelighting devices, the memory of the hub device 280, the memory of thenetwork device 290, memory of an external server, etc.). The lightingdevices and/or the hub device 280 may send and/or set the power statesof the lighting devices to the obtained prior power states of thelighting devices.

The remote control device 270 may include an internal sensing circuitcapable of detecting a state change event of a lighting device (e.g.,the light bulb 212), which may be caused by, for example, a powerremoval event (e.g., a system power removal event) or other controlevent (e.g., a command received by the light bulb 212 from the remotecontrol device 150). During a power removal event, the remote controldevice 270 may also be capable of detecting, in response to the internalsensing circuit, when power has been removed (e.g., in response todetecting when a light bulb turns from on to off) and when power hasbeen restored (e.g., in response to detecting when a light bulb turnsfrom off to on). The remote control device 270 may be battery-powered.If, for example, the remote control device 270 is battery-powered, theremote control device 270 may be powered (e.g., may still be powered)during a system power removal event and may be able to detect the systempower removal event. For example, when the remote control device 270 ismounted over the wall-mounted load control device 210 that suppliespower to the light bulb 212, power may not be removed from the lightbulb as a result of a local power removal event. If the light bulb 212is not controlled by another control devices and the remote controldevice 270 detects a state change event (e.g., via the internal sensingcircuit), the remote control device determine that a system powerremoval event occurred. Also, or alternatively, the light bulb 212 maybe controlled by another control device (e.g., such as the remotecontrol device 250). If the light bulb 212 is also controlled by theremote control device 250, the remote control device 270 may communicatewith the light bulb 212 to determine whether the state change (e.g.,from on to off) was triggered by the remote control device 250. If theinternal sensing circuit detects a state change event that is nottriggered by a command received from another control device (e.g., suchas the remote control device 270), the remote control device determinethat a system power removal event occurred.

For example, the internal sensing circuit may include a photosensingcircuit (e.g., a photosensor) capable of measuring the amount of and/ordetecting the presence and/or absence of light within the area in whichthe remote control device 270 is located (e.g., light emission). Theremote control device 270 may comprise a lens for directing the light inthe area to the photosensing circuit. The remote control device 270 maybe situated proximate and/or oriented to allow the photosensing circuitto measure light emitted by to a lighting device (e.g., the light bulb212). The remote control device 270 may be configured to detect a statechange event and/or a system power removal event in response todetecting a positive change in the measured light level (e.g., inresponse to the light bulb 212 turning from off to on) or a negativechange in the measure light level (e.g., in response to the light bulb212 turning on to off) via the photosensing circuit. During a powerremoval event, the remote control device 270 may use the photosensingcircuit to detect when power has been removed (e.g., in response todetecting a positive change in the measured light level) and when powerhas been restored (e.g., in response to detecting a negative change inthe measured light level).

The internal sensing circuit may also include a line power sensingcircuit (e.g., a mains voltage sensing circuit and/or a mains currentsensing circuit). The line power sensing circuit may be capable ofdetecting a change (e.g., a decrease and/or increase) in the mainsvoltage and/or mains current (e.g., load current) being supplied to thelighting device (e.g., the light bulb 212). For example, the line powersensing circuit may detect when current begins to flow and/or stopsflowing through the wall-mounted load control device 210 and/or theelectrical wiring connected to the lighting device (e.g., via a Halleffect sensor). For example, the light bulb 212 may include a capacitor,which may conduct a large inrush current (e.g., a spike of current) whenthe light bulb 212 is turned on. These spikes in current may generate amagnetic field. The magnetic field may be detectable by the line powersensing circuit. For example, the remote control device 270 may beconfigured to detect a state change event and/or a system power removalevent in response to detecting a positive change in the magnitude of themains current (e.g., in response to the light bulb 212 turning from offto on) or a negative change in the magnitude of the mains current (e.g.,in response to the light bulb 212 turning on to off) via the line powersensing circuit. During a power removal event, the remote control device270 may use the line power sensing circuit to detect when power has beenremoved (e.g., in response to detecting a positive change in themagnitude of the mains current) and when power has been restored (e.g.,in response to detecting a negative change in the magnitude of the mainscurrent).

As described herein, a lighting device (e.g., the light bulb 212) may becontrolled by multiple devices. If the lighting device is controlled bymultiple devices, the remote control device 270 may communicate with thelighting device to determine whether a state change event was caused bya power removal event (e.g., a system power removal event) or othercontrol event (e.g., a command received from the remote control device150). For example, upon detection of a state change event by theinternal sensing circuit (e.g., the photosensing circuit or the linepower sensing circuit), the remote control device 270 may transit one ormore digital messages to determine whether the power removal event is asystem power removal event or a state change event. For example, if thelighting device responds to the digital message while the lightingdevice is turned off (e.g., powered, but not illuminated), the remotecontrol device 270 may determine that the power removal event is a statechange event. A lighting device that is turned off and responding todigital messages, may have been turned off by another device (e.g., alocal power removal event). If, however, the lighting device does notrespond to the digital message, the remote control device 270 maydetermine that the power removal event is a system power removal event.In that case, once the lighting device turns back on, the remote controldevice 270 may transmit a command to control the lighting device to itslast state (e.g., before the power outage).

If the power removal event is determined to be a system power removalevent (e.g., the lighting device does not respond to a digital messagefrom the remote control device 270), the remote control device 270 maydetermine a previous state of one or more of the lighting devices (e.g.,the light bulbs 212, 222) and perform state correction on the lightingdevices. For example, state correction may include setting one or moreof the lighting devices (e.g., the light bulbs 212, 222) to its stateprior to the system power removal event. State correction may beperformed after the lighting device turns back on (e.g., when the systempower removal ends). For example, the remote control device 270 maystore the previous state of the lighting device and set the lightingdevice to the previous state after the lighting device turns back on.

FIG. 2D shows a load control system 200 c including additional controldevices (e.g., input devices, load control devices, and/or controllerdevices). The load control system 200 c may include other load controldevices, which may operate similar to other load control devicesdescribed herein. Examples of other load control devices may include adaylight control device, e.g., a motorized window treatment 230, mountedin front of a window for controlling the amount of daylight entering thespace in which the load control system 200 c is installed. The motorizedwindow treatment 230 may include, for example, a cellular shade, aroller shade, a drapery, a Roman shade, a Venetian blind, a Persianblind, a pleated blind, a tensioned roller shade systems, or othersuitable motorized window covering. The motorized window treatment 230may include a motor drive unit 232 for adjusting the position of acovering material 234 of the motorized window treatment in order tocontrol the amount of daylight entering the space. The motor drive unit232 of the motorized window treatment 230 may have an RF receiver and anantenna mounted on or extending from a motor drive unit of the motorizedwindow treatment. The motor drive unit 232 of the motorized windowtreatment 230 may be battery-powered or may receive power from anexternal direct-current (DC) power supply. Examples of battery-poweredmotorized window treatments are described in greater detail incommonly-assigned U.S. Patent Application Publication No. 2012/0261078,published Oct. 18, 2012, entitled MOTORIZED WINDOW TREATMENT, and U.S.Patent Application Publication No. 2014/0231032, published Aug. 21,2014, entitled BATTERY-POWERED ROLLER SHADE SYSTEM, the entiredisclosures of which are hereby incorporated by reference

The load control system may include other input devices that may operatesimilar to the input devices described herein. For example, the loadcontrol system 200 c may include an occupancy sensor 260. The occupancysensor 260 may be configured to detect occupancy and vacancy conditionsin the space in which the load control system 200 c is installed. Theoccupancy sensor 260 may transmit digital messages to the wall-mountedload control device 210 via the RF signals 206 in response to detectingthe occupancy or vacancy conditions. The wall-mounted load controldevice 210 may be configured to turn on the light bulb 212 in responseto receiving an occupied command. The wall-mounted load control device210 may be configured to turn off the respective light bulb in responseto receiving a vacant command. The occupancy sensor 260 may operate as avacancy sensor to turn off (e.g., only turn off) the lighting devices inresponse to detecting a vacancy condition (e.g., to not turn on thelight bulb 212 in response to detecting an occupancy condition).Examples of RF load control systems having occupancy and vacancy sensorsare described in greater detail in commonly-assigned U.S. Pat. No.8,009,042, issued Aug. 30, 2011, entitled RADIO-FREQUENCY LIGHTINGCONTROL SYSTEM WITH OCCUPANCY SENSING; U.S. Pat. No. 8,199,010, issuedJun. 12, 2012, entitled METHOD AND APPARATUS FOR CONFIGURING A WIRELESSSENSOR; and U.S. Pat. No. 8,228,184, issued Jul. 24, 2012, entitledBATTERY-POWERED OCCUPANCY SENSOR, the entire disclosures of which arehereby incorporated by reference.

The load control system 200 c may include a daylight sensor 262. Thedaylight sensor 262 may be configured to measure a total light intensityin the space in which the load control system is installed. For example,the daylight sensor may include an internal photosensing circuit capableof detecting changes in measurements of a total light intensity in thespace. For example, the daylight sensor may detect the changes in themeasurements of the total light intensity caused by the light bulbs 212,222. The daylight sensor 262 may transmit digital messages including themeasured light intensity to the wall-mounted load control device 210.The daylight sensor 262 may transmit digital messages via the RF signals206 for controlling the intensities of the light bulb 212 in response tothe measured light intensity. Examples of RF load control systems havingdaylight sensors are described in greater detail in commonly-assignedU.S. Pat. No. 8,410,706, issued Apr. 2, 2013, entitled METHOD OFCALIBRATING A DAYLIGHT SENSOR; and U.S. Pat. No. 8,451,116, issued May28, 2013, entitled WIRELESS BATTERY-POWERED DAYLIGHT SENSOR, the entiredisclosures of which are hereby incorporated by reference.

The load control devices (e.g., the lightbulbs 212, 222, the motorizedwindow treatment 230, etc.) may be two-way communication devices and mayreceive the power removal event message and/or power state message. Forexample, load control devices may receive messages (e.g., power removalevent messages and/or power state messages), and/or may acknowledgereceipt of the messages (e.g., power removal event messages and/or powerstate messages) to the transmitting device. The load control devices mayidentify the power removal event message and/or power state message asbeing from the hub device 280, a lighting device, and/or the networkdevice 290. The load control devices may identify the hub device 280, alighting device, and/or a network device 290 by a device identifier(unique identifier).

The input devices (e.g., the occupancy sensor 260, daylight sensor 262,remote control device 250, remote control device 270 etc.) may beone-way or two-way communication devices. The input devices that aretwo-way communication devices may receive the power removal eventmessage and/or power state message. The input devices that are one-waycommunication devices may be unable to receive the power removal eventmessage and/or the power state message. The one-way communicationdevices may transmit power state information and/or power removal eventinformation. The power state information and/or the power removal eventinformation may include the identifier of the transmitting device. Totransmit the power state information and/or power removal eventinformation, a button on the one-way communication device may beactuated or the device may identify a power startup at the device. Totrigger the transmission of power state information and/or power removalevent information at the daylight sensor 262, the daylight sensor maydetect a changes in the measured light level. The daylight sensor 262may be a sensor that is external to other devices in the system (e.g.,remote control device 270, hub device 280 and/or other devices in thesystem) and capable of measuring light levels in the space. Though somecontrol devices may be described as one-way or two-way communicationdevices, any control device may include a button and/or sensing circuitfor triggering the transmission of power state information and/or powerremoval event information.

The control devices (e.g., lighting devices, the battery-powered remotecontrol device 250, the occupancy sensor 260, the daylight sensor 262,the remote control device 270, the hub device 280, and/or the networkdevice 290, etc.) may communicate with one another via one or morecommunication protocols. For example, the lighting devices, thebattery-powered remote control device 250, the occupancy sensor 260, thedaylight sensor 262, and the remote control device 270 may be capable ofcommunicating with the hub device 280 and/or the network device 290 viawireless signals (e.g., RF signals), such as WI-FI® signals; WIMAX®signals; BLUETOOTH® signals; near field communication (NFC) signals;proprietary communication signals, such as CLEAR CONNECT™; ZIGBEE®signals, Z-WAVE signals, and/or the like. Each control device may becapable of communicating on the same protocol and/or frequencies. Eachcontrol device may be capable of communicating on different protocolsand/or frequencies. For example, the occupancy sensor 260 and/or thedaylight sensor 262, and the motorized window treatment 230 maycommunicate via one protocol or frequency (e.g., a proprietary protocol,such as CLEAR CONNECT™), the remote control device 270, thebattery-powered remote control device 250, and/or the light bulbs 212,222 may communicate via one protocol or frequency (e.g., ZIGBEE®,BLUETOOTH, etc.), and/or the network device 290 may communicate via oneprotocol or frequency (e.g., WI-FI®, cellular, etc.). The occupancysensor 260, the daylight sensor 262, and/or the motorized windowtreatment 230 may communicate using the same or different protocol orfrequency as the remote control device 270, the battery-powered remotecontrol device 250, and/or the light bulbs 212, 222. An intermediatedevice (e.g., the hub device 280) may be used to allow communicationbetween one or more devices communicating using one or morecommunication protocols.

The remote control device 270 may be coupled to and/or mounted over thetoggle actuator 216 of the wall-mounted load control device 210 (e.g.,as described above). The load control devices (e.g., the light bulbs212, 222, the motorized window treatment 230, etc.) may experience apower removal event. To determine whether a power removal event is alocal power removal event or a system power removal event, the powerstates of one or more of the control devices and/or the hub device 280may be determined. For example, if the light bulb 212 is experiencing apower removal event and one or more of the other control devices areexperiencing a power removal event, it may be determined that the powerremoval event is a system power removal event. If control devicespositioned within one or more rooms are experiencing a power removalevent, it may be determined that the power removal event is a systempower removal event. If the light bulb 212 is experiencing a powerremoval event and other control devices are not experiencing a powerremoval event, it may be determined that the power removal event is alocal power removal event. The lighting devices and/or the hub device280 may determine the power states of one or more control devices.

A power removal detection device may be configured to detect a statechange event and determine whether the state change event is the resultof system power removal event (e.g., power removal event detection). Asdescribed herein, a device configured to perform power removal eventdetection may be a power removal detection device. Power removal eventdetection may be performed by devices other than the remote controldevice 270. For example, power removal event detection may be performedby the hub device 280. For example, to determine if a power removalevent is a system power removal event, the hub device 280 may include aninternal sensing circuit, such as a line voltage sensing circuit, fordetermining if the mains voltage generated by the AC power source 202 ispresent. In addition, the hub device 280 may comprise a photosensingcircuit capable of detecting a state change event of a lighting device(e.g., the light bulb 212), which may be caused by, for example, a powerremoval event (e.g., a system power removal event) or other controlevent (e.g., a command received by the light bulb 212 from the remotecontrol device 150). In addition, the hub device 280 may receivemessages from one or more of the input devices (e.g., the occupancysensor 260, the daylight sensor 262, the remote control device 270,etc.) indicating a state change event of a lighting device (e.g., thelight bulb 212).

The hub device 280 may be powered from the AC power source 202 (e.g.,via the electrical plug 220 plugged into the electrical receptacle 226).In addition, the hub device 280 may include a power source other thanfrom line voltage (e.g., so that if a system power removal event occurs,the hub device 280 may still be powered and/or functional). For example,the hub device 280 may include a battery backup, which may be used forpower when a system power removal event occurs. Also, or alternatively,the hub device 280 may be solely powered by an alternative power sourceother than line voltage.

The hub device 280 may operate as a power removal event detection deviceand may be in communication with multiple input devices (e.g., theoccupancy sensor 260, the daylight sensor 262, the remote control device250, the remote control device 270 etc.) and/or multiple load controldevices (e.g., the light bulbs 212, 222, the motorized window treatment230, etc.). The hub device 280 may receive one or more messagesindicating a state change event. The hub device 280 may be configured todetermine whether the state change event is the result of a system powerremoval event or another control event (e.g., a command received by thelight bulb 212 from the remote control device 150). For example, whenthe hub device 280 receives messages from multiple daylight sensorsindicating that each of the multiple lighting devices have experienced astate change event (e.g., each of the lighting devices are unpowered),the hub device 280 may determine that a system power removal event hasoccurred. Also, or alternatively, the hub device 280 may use internalsensing circuit (e.g., a photosensing circuit or a line power sensingcircuit) to determine whether a state change event is the result of asystem power removal event or another control event. For example, asdescribed herein, the hub device 280 may include an internal sensingcircuit, such as a line voltage sensing circuit, for determining if themains voltage generated by the AC power source 202 is present. When thehub device 280 determines that the power removal event is a system powerremoval event, the hub device 280 may perform state correction for thelighting devices (e.g., the light bulbs 212, 222).

FIG. 3 is a simplified flowchart depicting an example method 300 forretaining and/or adjusting power state information for lighting devices(e.g., the light bulb 212 and/or the light bulb 222). The method 300 maydepict an example method for retaining and/or adjusting power stateinformation for lighting devices based on whether an operation mode(e.g., a switched mode) is set. As shown in FIG. 3, the method 300 maybegin at 302. At 304, the lighting device and/or the hub device 280 maydetermine if the lighting device has encountered a power removal event.For example, the lighting device and/or the hub device 280 may determineif the lighting device has encountered a loss of power, such asblackout, a brownout, or another activity that has removed electricalpower from the lighting device. The lighting device and/or the hubdevice 280 may determine information regarding the power removal event.For example, the lighting device and/or the hub device 280 may determinethe time at which the power removal event occurred, the time at whichpower was last regained, the duration of the power removal event, and/orthe duration since the power removal event ended.

If the lighting device determines that a power removal event has notoccurred, the method may move to 306. At 306, the lighting device maydetermine whether power state information has been received. The powerstate information may include an on power state, an off power state, anintensity state, a color state, etc. For example, at 306, the lightingdevice may determine whether the lighting device has received powerstate information of an intensity of sixty percent. The power stateinformation may be received via one or more digital messages. Forexample, a lighting device may receive power state information from acontrol device, a network device, a hub device, etc.

If power state information is received at 306, the lighting device mayadjust its state, at 308. The lighting device may adjust its state basedon the received power state information. For example, a lighting devicemay set its state to an intensity of sixty percent if the devicereceives a digital message including a request for the lighting deviceto set its state to an intensity of sixty percent. The lighting devicemay, at 310, store the received power state information. The lightingdevice may store the power state internally (e.g., in memory of thelighting device). The lighting device may store the power stateexternally (e.g., on an external device, such as another lightingdevice, a hub device, an external server, etc.). The method may returnto 304 to determine if a power removal event has occurred.

If, at 304, it is determined that a power removal event has occurred(e.g., the lighting device and/or the hub device 280 determines that apower removal event has occurred), the lighting device and/or the hubdevice 280 may determine, at 312, whether an operation mode is set. Forexample, the lighting device and/or the hub device 280 may determinewhether a switched mode is set and/or whether an unswitched mode is set.The switched mode may indicate that the lighting device is capable ofbeing controlled by a switch (e.g., the toggle actuator 216 coupled tothe wall-mounted load control device 210). The unswitched mode mayindicate that the lighting device is incapable of being controlled(e.g., turned off and/or turned on) by a switch, such as toggle actuator216. If, at 312, the control is not set to the unswitched mode, thelighting device and/or the hub device 280 may set the power state of thelighting device to a predetermined state (e.g., an on power state at apredetermined intensity state) at 318. For example, if the lightingdevice is not set to the unswitched mode, the lighting device and/or thehub device 280 may set the state of the lighting device to a fullintensity level, a defined intensity state, and/or the prior powerstate. After setting the power state at 318, the method may return to304 to determine if a power removal event has occurred.

If, at 312, the unswitched mode is set, the method 300 may move to 314.At 314, the lighting device and/or the hub device 280 may retrieve apower state of the lighting device. The power state of the lightingdevice may be a prior power state of the lighting device (e.g., a powerstate prior to the power removal event). For example, if the lightingdevice and/or the hub device 280 determines that a power removal eventhas occurred, at 304, the lighting device and/or the hub device 280 mayretrieve the power state that the lighting device and/or the hub device280 previously and stored at 310. At 316, the lighting device may adjustits power state to the power state retrieved at 314. As an example, at316, the lighting device may adjust its power state to an intensity ofsixty percent if the prior power state was an intensity of sixtypercent. After setting the power state at 316, the method may return to304 to determine if a power removal event has occurred.

FIG. 4 is a simplified flowchart depicting an example method 400 forretaining and/or adjusting state information (e.g., power stateinformation) of one or more lighting devices (e.g., the light bulb 212and/or the light bulb 222). The method 400 may depict an example methodfor retaining and/or adjusting state information of one or more lightdevices, based on whether a power removal event is a local power removalevent or a system power removal event. For example, method 400 maydepict an example method for retaining and/or adjusting stateinformation (e.g., power state information) of lighting devices using ahub device (such as the hub device 280). As shown in FIG. 4, the method400 may begin at 402. At 404, the hub device may determine if thelighting device has encountered a power removal event. For example, thehub device may determine if the lighting device has encountered ablackout, a brownout, or another activity (such as a user physicallyturning off a switch to a lighting load) that has removed electricalpower from the lighting device. The hub device may determine informationregarding the power removal event. For example, the hub device maydetermine the time at which the power removal event occurred, theduration of the power removal event, and/or the duration since the powerremoval event ended.

If the hub device determines that a power removal event has notoccurred, the method may move to 406. At 406, it may be determinedwhether power state information is received. The power state informationmay include information relating to the power state of the hub device280, and/or the power state information may include information relatingto the power state of one or more lighting devices. The power stateinformation may include an on power state, an off power state, anintensity state, a color state, etc. For example, at 406, the lightingdevice may determine whether the hub device and/or the lighting devicehas received power state information of an intensity of sixty percent.The power state information may be received via one or more digitalmessages. For example, a lighting device may receive power stateinformation from a control device, a network device, a hub device, etc.

If power state information is received at 406, the received power stateinformation may be stored at 408. The lighting device may store thepower state internally (e.g., in memory of the lighting device). Thepower state may be stored externally (e.g., on an external device, suchas another lighting device, a hub device, an external server, etc.).

If power state information is received at 406, the lighting device mayadjust its power state at 410. The lighting device may adjust its powerstate based on the received power state information. For example, alighting device may set its state to an on power state if the lightingdevice receives a digital message including a request for the lightingdevice to set its state to an on power state. If the power stateinformation is not received at 406, or is received and the lightingdevice has performed adjustments, the method 400 may return to 404 todetermine if a power removal event has occurred.

If, at 404, it is determined that a power removal event has occurred(e.g., the hub device 280 determines that a power removal event hasoccurred), the hub device 280 may determine, at 412, whether the powerremoval event is a system power removal event, at 412. The hub device280 may determine that a power removal event is a system power removalevent (e.g., a brownout and/or a blackout) by querying lighting devicespositioned at different locations and/or by querying lighting devicesthat are within groups positioned at different locations. For example,the hub device 280 may query lighting devices connected to differentcircuits (e.g., AC circuits) to determine if the power removal event isa system power removal event (e.g., a power removal event affecting morethan one AC circuit, such as a brownout or blackout) and/or whether thepower removal event is a local power removal event (e.g., a powerremoval event affecting a single AC circuit, such as when a userphysically turns off a switch to a lighting device, for example).

If, at 412, the power removal event is determined to not be a systempower removal event, the lighting device may set the state of thecontrol device to a predetermined state (e.g., an on power state at apredetermined intensity state), at 418. For example, if the powerremoval event is determined to not be a system power removal event, thelighting device may set the state of the lighting device to a fullintensity level, a defined intensity state, and/or the prior powerstate. After setting the power state at 418, the method may return to404 to determine if a power removal event has occurred

If, at 412, the power removal event is determined to be a system powerremoval event, move to 414. At 414, the lighting device may retrieve apower state of the lighting device. The power state of the lightingdevice may be a prior power state of the lighting device (e.g., a powerstate prior to the power removal event). For example, if the lightingdevice and/or the hub device 280 determines that a system power removalevent has occurred, at 410, the lighting device and/or the hub device280 may retrieve the power state that the lighting device previouslystored at 410. At 416, the lighting device may adjust its power state tothe power state retrieved at 414. As an example, at 416, the lightingdevice may adjust its power state to an intensity of sixty percent ifthe prior power state was an intensity of sixty percent. After settingthe power state at 416, the method may return to 404 to determine if apower removal event has occurred.

FIG. 5 is a simplified flowchart depicting an example method 500 forassociating a lighting device (e.g., the light bulb 212 and/or the lightbulb 222) with a retrofit remote control device (e.g., the retrofitremote control device 270). For example, the method 500 may be executingby the lighting device for determining whether state information (e.g.,power state information) of one or more control devices is to beadjusted and/or retained, based on the use of the retrofit remotecontrol device 270. The retrofit remote control device may be configuredto be coupled to a toggle actuator of a light switch (e.g., the toggleactuator 216 of the wall-mounted load control device 210) that iscoupled in series electrical connection with the lighting device. Theretrofit remote control device may be configured to retain the lightswitch in an on position. The retrofit remote control device maycommunicate with the lighting device, for example, via one or more ofthe devices via wireless signals, e.g., radio-frequency (RF) signals 206(e.g., ZIGBEE®; NFC; BLUETOOTH®; WI-FI®; or a proprietary communicationchannel, such as CLEAR CONNECT™, etc.).

As shown in FIG. 5, the method 500 may begin at 502. At 504, anassociation message may be received. For example, at 504, the lightingdevice may receive an association message. The association message maybe sent by one or more devices. For example, the association message maybe sent by control devices (e.g., lighting devices, remote controldevices, etc.) and/or hub devices.

The association message may be transmitted from a device in anassociation mode. The association message may indicate a uniqueidentifier of the device and/or a device type from which the associationmessage is transmitted. For example, an association message from alighting device may indicate that the message is from a lighting device,an association message from a wall-mounted dimmer may indicate that themessage is from a wall-mounted dimmer, and/or an association messagefrom a retrofit remote control device may indicate that the message isfrom a retrofit remote control device. The device type may be indicatedby the unique identifier, or a separate identifier. The associationmessage may indicate the location of the device in the load controlsystem from which the association message is received. The associationmessage may identify the devices that are coupled to and/or associatedwith the device from which the association message is sent. For example,a device may send association information, including the identificationof devices and/or device types, stored on the device during associationand from which the device may receive digital messages for performingcontrol.

At 506, it may be determined if the association message was receivedfrom a retrofit remote control device. The association message mayindicate the other control devices with which the retrofit device isassociated. For example, if the lighting device receives an associationmessage from a retrofit remote control device during an associationmode, the lighting device may be associated with the retrofit device.The lighting device may also identify the retrofit remote control deviceas being previously associated with another lighting device fromassociation information indicating previous associations. Based on theassociation information, the lighting device may determine the locationof the retrofit remote control device and/or the other control devices(e.g., lighting devices) to which the retrofit remote control device isassociated.

If, at 506, it is determined that a retrofit device is not being used,the method 500 may move to 510. If, at 506, it is determined that aretrofit device is being used, an operation mode may be set at 508(e.g., an unswitched mode may be set). The unswitched mode may indicatethat the lighting device is incapable of being controlled (e.g., turnedoff and/or turned on) by a switch (e.g., the wall-mounted load controldevice 210 shown in FIG. 2). For example, the unswitched mode mayindicate that the lighting device is not downstream of a light switchthat is capable of being switched off at the time. The unswitched modemay indicate that the lighting device is downstream of a light switch towhich a retrofit remote control device is mounted, where the retrofitremote control device may retain the light switch in the on position.

At 510, association information received in the association message at504 may be stored. For example, at 510, a unique identifier (e.g.,serial number) of the retrofit remote control device and/or theassociated control devices (e.g., a lighting device, such as light bulb212) may be stored. The association information may include the uniqueidentifier (e.g., serial number) of other devices, the device types,locations, etc. of devices. The association information may be stored bythe hub device 280, a lighting device, and/or the network device 290.The association information may be stored so that the hub device 280,the lighting devices, and/or the network device 290 may determine thecontrol devices that are associated with a retrofit remote controldevice. The association information may be stored so that the hub device280, the lighting devices, and/or the network device 290 may identifythe control devices that are unassociated with a retrofit remote controldevice.

If a control device (e.g., lighting device) is associated with aretrofit remote control device, the control device may be determined tohave experienced a system power removal event if the control deviceexperiences a power removal event. For example, if the light bulb 212 isassociated with the retrofit remote control device 270 and the lightbulb 212 experiences a power removal event, it may be determined thatthe light bulb 212 has experienced a system power removal event. Thelight bulb 212 may be determined to have experienced a system powerremoval vent because the retrofit remote control device 270 isconfigured to maintain the toggle actuator 216 of the wall-mountedremote control device 210 in the on position and the power state of thelight bulb 212 in the on power state. For example, if the retrofitremote control device 270 is configured to prevent a user from actuatingthe toggle actuator 216 in the on position and the wall-mounted remotecontrol device from turning off the light bulb 212, the light bulb 212may be turned to an off power state during a system power removal event(e.g., brownout, blackout, etc.). The light bulb 212 may be preventedfrom being turned off based on a local power removal event (e.g.,turning the toggle actuator 216 to the off position). If the light bulb212, other lighting devices, and/or the hub device 280 determines thatthe light bulb 212 has experienced a power removal event, the light bulb212, the other lighting devices, and/or the hub device 280 may determinethat the power removal event of the light bulb 212 is a system powerremoval event. The method may end at 512.

FIG. 6 is a simplified flowchart of an example procedure 600 fordetecting and flagging power removal events (e.g., system power removalevents). The procedure 600 may be performed by a control device, such asa remote control device (e.g., the remote control device 270) and/or ahub device (e.g., the hub device 280). Also, or alternatively, theprocedure 600 may be performed in conjunction by both the remote controldevice and the hub device. For example, certain steps in the procedure600 may be performed by the remote control device while other steps inthe procedure 600 may be performed by the hub device.

The procedure 600 may begin at 602. At 604, the control device maydetect a condition indicating that a lighting device (e.g., one or bothof the light bulbs 212, 222) has changed states to turn from on to off(e.g., a state change event). As described herein, the control devicemay detect that the lighting device has changed from on to off via aninternal sensing circuit (e.g., a photosensing circuit and/or a linepower sensing circuit). For example, if the internal sensing circuit isa photosensing circuit, the control circuit may measure the lightemitted by the lighting device via the photosensing circuit to detect acondition indicating that that the lighting device has changed statesfrom on to off. If the internal sensing circuit is a line power sensingcircuit, the control device may detect changes in the mains currentconducting through the lighting device to detect a condition indicatingthat the lighting device has changed states from on to off. Also, oralternatively, the control device may detect that the lighting devicehas changed states from on to off by receiving or more messages. Forexample, the control device may receive one or more messages thatindicate the lighting device has experienced a state change event fromone or more external input devices (e.g., the daylight sensor 262, theremote control device 250, the remote control device 270, etc.). Asdescribed herein, the messages may be received from multiple daylightsensors and/or may indicate that one or more lighting devices havechanged states from on to off. For example, when a daylight sensordetects that the lighting devices have changed states from on to off(e.g., a state change event), the daylight sensor may generate and/ortransmit a message indicating that a state change event has occurred.

As described herein, multiple devices (e.g., the remote control device270, the hub device 282, and/or the remote control device 250) maycontrol the lighting device. Accordingly, the condition indicating thelighting device has changed states from on to off may be a result of thelighting device receiving control instruction to turn off from one ofthe multiple control devices, or a system power removal event. At 606,to determine whether the state change event is the result of a systempower removal event or another control event, the control device maytransmit a query to the lighting device. After transmitting the query at608, the control device may receive a response from the lighting deviceat 608 or a timeout may expire at 610. Reception of a response from thelighting device may indicate that the change state event was caused bythe lighting device receiving control instruction to turn off from oneof the multiple control devices (e.g., a control event). For example,the lighting device may send a response if the lighting device iselectrically powered even if the lighting device is turned to an offstate. For example, the lighting device may be electrically powered butturned off in response to receiving control instructions from anotherremote control device. Alternatively, expiration of the timeout mayindicate that the change state event was caused by a system powerremoval event. For example, if the control device does not receive aresponse from the lighting device within a certain amount of time (e.g.,the timeout), the control device may determine that the lighting deviceis unpowered (e.g., a system power removal event occurred). If a timeoutexpires before a response to the query is received, the control devicemay flag the lighting device as unpowered in memory at 612. After eitherreceiving a response to the query from the lighting device at 608 orflagging the lighting device as unpowered at 612, the procedure 600 mayend.

As described herein, the procedure 600 may be used to detect statechange events and/or determine whether the state change event was causedby a lighting device receiving control instruction to turn off from oneof the multiple control devices (e.g., a control event) or a systempower removal event. Detecting a system power removal event may allow acontrol device (e.g., remote control device 270 and/or hub device 280)to track and/or store the lighting devices that are experiencing asystem power removal event. Further, tracking lighting devices that areexperiencing system power removal events may allow the control device toperform state correction after the lighting device regains power (e.g.,setting the lighting device to its state prior to the power removalevent).

FIG. 7 is a simplified flowchart of an example procedure 700 forperforming state correction after a power removal event (e.g., a systempower removal event). For example, state correction may include settinga lighting device that has experienced a system power removal event tothe state of the lighting device prior to the system power removalevent. The procedure 700 may be executed when a state change event isdetected after a system power removal event occurs (e.g., afterprocedure 600 determines that system power removal event occurred and/orthe lighting device is flagged as unpowered). For example, the procedure700 may be executed when a lighting device turns on (e.g., a statechange event is detected). The procedure 700 may be performed by acontrol device, such as a remote control device (e.g., the remotecontrol device 270) and/or a hub device (e.g., the hub device 280).Also, or alternatively, the procedure 700 may be performed inconjunction by both the remote control device and the hub device. Forexample, certain steps in the procedure 700 may be performed by theremote control device and other steps in the procedure 700 may beperformed by the hub device.

The procedure 700 may begin at 702. At 704, the control device maydetect a condition indicating that a lighting device (e.g., one or bothof the light bulbs 212, 222) has changed states to turn from off to on(e.g., a state change event). As described herein, the control devicemay detect that the lighting device has turned on via an internalsensing circuit (e.g., a photosensing circuit or a line power sensingcircuit). Also, or alternatively, the control device may detect that thelighting device has turned on by receiving or more messages. Forexample, the control device may receive messages indicating the lightingdevice has turned on from one or more external input devices (e.g., theoccupancy sensor 260, daylight sensor 262, remote control device 250,remote control device 270 etc.). Also, or alternatively, the lightingdevice may be configured to broadcast one or more messages after turningon, and the control device may receive the message indicating that thelighting device has turned on.

At 706, the control device may determine whether the lighting device isflagged as unpowered in memory (e.g., flagged as experiencing a systempower removal event). If, at 706, the lighting device is flagged asunpowered, the control device may retrieve a power state for thelighting device at 708. The power state of the lighting device may be aprior power state of the lighting device (e.g., a power state prior tothe system power removal event). The control device may also toggle theflag to indicate that the lighting device is no longer unpowered (e.g.,no longer experiencing a system power removal event) at 709. At 710,based on the power state retrieved at 708, the control device may adjustthe lighting device to the retrieved power state (e.g., by transmittingone or more messages to the lighting device).

After turning back on, a lighting device that experienced a powerremoval event may be set to an inaccurate lighting level. For example,although the lighting device is to be set to an 80% intensity level,after regaining power the lighting device may output light at 100%.Similarly, although the lighting device is to be set to a 0% intensitylevel, after regaining power, the lighting device may output light at a100% intensity level. If the lighting device is set to an inaccuratelighting level, lighting devices in the load control system may not beuniform, which may provide a poor user experience. Also, oralternatively, if the lighting device is set to an inaccurate lightinglevel, the lighting devices may be set to a state wholly opposite fromthe state intended by the user (e.g., the lighting device is set to a100% intensity level after experiencing a system power removal event inthe middle of the night and when the lighting device should be set to a0% intensity level). As described herein, the procedure 700 may setlighting devices to the desired intensity level after experiencing asystem power removal event and/or provide a positive user experience.

FIG. 8 is another simplified flowchart of an example procedure 800 fordetecting power removal events (e.g., system power removal events) andfor performing state correction after the system power removal event hasended. The procedure 800 may determine whether a lighting device hasexperienced a system power removal event when a state change eventoccurs (e.g., a light turns on). The procedure 800 may be performed by acontrol device, such as a remote control device (e.g., the remotecontrol device 270) and/or a hub device (e.g., the hub device 280).Also, or alternatively, the procedure 800 may be performed inconjunction by both the remote control device and the hub device. Forexample, certain steps in the procedure 800 may be performed by theremote control device and other steps in the procedure 800 may beperformed by the hub device. Detecting whether the lighting deviceexperienced a system power removal event when a state change eventoccurs may allow the control device to perform system power removalevent detection and state correction contemporaneously (e.g., ratherthan detecting a system power removal event when the lighting deviceturns off and then waiting for the light to turn back on to performstate correction).

The procedure 800 may begin at 802. At 804, the control device maydetect a condition indicating that a lighting device (e.g., light bulb212, 222) has changed states to turn from off to on (e.g., a statechange event). As described herein, the control device may detect thatthe lighting device has turned on via an internal sensing circuit (e.g.,a photosensing circuit or a line power sensing circuit). Also, oralternatively, the control device may detect that the lighting devicehas turned on by receiving or more messages. For example, the controldevice may receive messages from one or more external input devices(e.g., the occupancy sensor 260, daylight sensor 262, remote controldevice 250, remote control device 270 etc.). Also, or alternatively, asdescribed herein, the lighting device may be configured to broadcast oneor more messages after turning on, and the control device may receivethe message indicating that the lighting device has turned on.

If the control device determines that lighting device has just turned onat 804, the control device may transmit a query to the lighting deviceat 806 to determine if the lighting device was unpowered prior toturning on (e.g., experienced a system power removal event). Thelighting device itself may maintain and track its state and/or powerremoval event information and the query transmitted at 806 may requestthe lighting device's previous state information. For example, thelighting device may determine its previous state information and/or thatthe lighting device was previously unpowered during a startup routine.At 808, the lighting device may indicate whether it was unpowered priorto turning on (e.g., after experiencing a power removal event). Forexample, the lighting device may have been unpowered because of a systempower removal event. If the lighting device was not unpowered prior toturning on, the procedure 800 may end. If the lighting device wasunpowered prior to turning on (e.g., experienced a system power removalevent), the control device may retrieve a power state for the lightingdevice at 810. The power state of the lighting device may be a priorpower state of the lighting device (e.g., a power state prior to thesystem power removal event). The control device may also toggle the flagto indicate that the lighting device is no longer unpowered (e.g., nolonger experiencing a system power removal event) at 811.

After a lighting device regains power, a device (e.g., remote controldevice 270 and/or hub device 280) may perform state correction. Forexample, state correction may include retrieving a power state oflighting device (e.g., at 810, as illustrated in FIG. 8). The powerstate of the lighting device may be a prior power state of the lightingdevice (e.g., a power state prior to the system power removal event). At812, the lighting device may adjust its power state to the power stateretrieved at 810. As described herein, setting the lighting device to aprior power state after regaining power may allow for uniformity amongthe lighting devices in a load control system and/or may provide apositive user experience. For example, although the lighting device isto be set to an 80% intensity level, after regaining power the lightingdevice may output light at 100%. Similarly, although the lighting deviceis to be set to a 0% intensity level, after regaining power, thelighting device may output light at a 100% intensity level. If thelighting device is set to an inaccurate lighting level, lighting devicesin the load control system may not be uniform, which may provide a pooruser experience. Also, or alternatively, if the lighting device is setto an inaccurate lighting level, the lighting devices may be set to astate wholly opposite from the state intended by the user (e.g., thelighting device is set to a 100% intensity level after experiencing asystem power removal event in the middle of the night and when thelighting device should be set to a 0% intensity level). Referring toFIG. 8, for example, if the prior power state of the lighting device wasan intensity of sixty percent, the lighting device may adjust its powerstate to an intensity of sixty percent at 812.

Though the procedure 600 of FIG. 6 and the procedure 800 of FIG. 8 maydescribe sending a query to an individual lighting device, a query maybe sent to other lighting devices or other control devices. For example,when the control device or a hub device detects a condition indicatingthat a lighting device (e.g., one or both of the light bulbs 212, 222)has changed states to turn from on to off (e.g., a state change event),the control device or the hub device may query other control devices(e.g., other lighting control device(s)) additionally, or alternatively,to determine whether the state change event was a system power removalevent. If the other control devices respond to the query, then the statechange event may be determined not to be a system power removal event.If the other control devices fail to respond to the query, then thestate change event may be determined to be a system power removal event.

The control device or the hub device may also, or alternatively, listenfor digital messages being communicated in the load control system todetermine whether a system power removal event has occurred. Forexample, when the control device or a hub device identifies a digitalmessage being communicated to/from a load control device (e.g., one orboth of the light bulbs 212, 222) that has changed states to turn fromon to off (e.g., a state change event), the control device or the hubdevice may determine that the state change event was not a system powerremoval event. The control device or hub device may detect the statechange event and detect that one or more digital messages aretransmitted to/from the load control device within a predefined periodof time after the state change event. The predefined period of time maybe within seconds, milliseconds, or another time period less than thetime period for the device to power on and establish communications withother devices. The fact that the load control devices continue totransmit and/or receive messages from other devices may indicate thatthe device is powered on and failed to experience a system power removalevent upon the detection of the state change event. Since the

To determine whether the state change event was a system power removalevent, the control device or hub device may query the load controldevice identified as experiencing the state change event for anidentification of times at which messages were transmitted to/from theload control device. The load control device may keep a log of messagestransmitted to/from the load control device and send timestampsindicating the times at which messages were transmitted to/from the loadcontrol device. The control device or hub device may compare the timesat which messages were transmitted to/from the load control device withthe time at which the state change event was detected to determinewhether the state change event was a system power removal event.

The control device or the hub device may also, or alternatively,determine that the state change event was caused by the lighting devicereceiving control instruction to turn off from the control device or thehub device itself. For example, if the internal sensing circuit of thecontrol device or the hub device detects the state change event within apredefined period of time after transmitting a digital messageconfigured to turn the lighting device off, the control device or hubdevice may determine that the state change event is not a system powerremoval event. If the internal sensing circuit of the control device orthe hub device detects the state change event after the predefinedperiod of time, the control device or hub device may determine that thestate change event is a system power removal event.

Similarly, as described herein, the control device or hub device maylisten to the messages are transmitted to/from the lighting device orother load control devices in the system prior to a state change eventand use the information in the messages to determine whether the statechange event is a system power removal event. For example, the controldevice or hub device may identify messages that include controlinstructions that are sent to the load control device for changing thestate of the load control device (e.g., turning the lighting load off)from another device, or messages that are transmitted from the loadcontrol device that indicate a state change event has occurred (e.g.,status or heartbeat message). These messages may be detected before thestate change event and the control device or the hub device maydetermine that the subsequent state change event (e.g., occurring withina predefined period of time) at the load control device is not a systempower removal event. A lack of messages being transmitted to/from theload control device may be a factor of a number of factors describedherein in determining that the state change event is a system powerremoval event.

FIG. 9 is a block diagram illustrating an example control device 900,e.g., a load control device, as described herein. The control device 900may be a lighting device (e.g., the light bulb 212, such as shown inFIG. 2). The control device 900 may be a dimmer device, an electronicswitch, an electronic ballast for lamps, an LED driver for LED lightsources, an AC plug-in control device, a temperature control device(e.g., a thermostat), a motor drive unit for a motorized windowtreatment, or other control device. The control device 900 may comprisea load regulation circuit 908 that may control an electrical load 916.The electrical load 916 may include any type of electrical load. Forexample, the electrical load may be a lighting load and/or a lightingdevice. The load regulation circuit 908 may receive power via a hotconnection 912 and a neutral connection 914 (e.g., for connection to apower source, such as an AC power source) and may provide an amount ofpower to the electrical load 916. When the control device 900 is a lightbulb (e.g., such as the light bulb 212 and/or the light bulb 222), theelectrical load 916 may be integral to the control device 900. When thecontrol device 900 is a light bulb and the electrical load is, forexample, an LED light source, the load regulation circuit 908 maycomprise an LED drive circuit. When the control device 900 is a dimmerdevice (e.g., such as dimmer device 218, shown in FIG. 2B), theelectrical load 916 may be external to the control device (e.g., asshown in FIG. 9) and the control device may be coupled to the electricalload via a single electrical connection. The electrical load 916 may becoupled to the neutral side of the AC power source, and the controldevice 900 may not include the neutral connection 914 to the neutralside of the AC power source. When the control device 900 is a dimmerdevice, the load regulation circuit 908 may comprise a dimming circuitfor controlling the power delivered to the electrical load using aphase-control technique. The control circuit 904 may determine thestatus of the electrical load 916 in response to status feedbackreceived from the load regulation circuit 908.

The control device 900 may comprise a control circuit 904 that maycontrol the load regulation circuit 908 for controlling the electricalload 916. The control circuit 904 may include one or more generalpurpose processors, special purpose processors, conventional processors,digital signal processors (DSPs), microprocessors, integrated circuits,a programmable logic device (PLD), application specific integratedcircuits (ASICs), or the like. The control circuit 904 may performsignal coding, data processing, power control, input/output processing,or any other functionality that enables the control device 900 toperform as described herein. The control device 900 may include acommunications circuit 902. The communications circuit 902 may includean RF transceiver or other communications circuits capable of performingwired and/or wireless communications via a communications link (e.g., awireless or wired communication link). The communications circuit 902may be in communication with the control circuit 904. Though a singlecommunications circuit 902 may be described, the control device 900 mayinclude multiple communication circuits each configured to transmitand/or receive information.

The control circuit 904 may store information in and/or retrieveinformation from the memory 906. For example, the memory 906 maymaintain a registry of associated control devices and/or controlconfiguration instructions. The memory 906 may include a non-removablememory and/or a removable memory.

The control circuit 904 may be in communication with actuators 918(e.g., one or more buttons) that may be actuated by a user tocommunicate user selections to the control circuit 904. For example, theactuators 918 may be actuated to put the control circuit 904 in anassociation mode and/or communicate association messages from thecontrol device 900.

FIG. 10 is a block diagram illustrating an example input device 1000 asdescribed herein. The input device 1000 may be a remote control device(such as remote control device 250 and/or remote control device 270), anoccupancy sensor, a daylight sensor, a window sensor, a temperaturesensor, and/or the like. The input device 1000 may include a controlcircuit 1002 for controlling the functionality of the input device 1000.The control circuit 1002 may include one or more general purposeprocessors, special purpose processors, conventional processors, digitalsignal processors (DSPs), microprocessors, integrated circuits, aprogrammable logic device (PLD), application specific integratedcircuits (ASICs), or the like. The control circuit 1002 may performsignal coding, data processing, power control, input/output processing,or any other functionality that enables the input device 1000 to performas described herein.

The control circuit 1002 may store information in and/or retrieveinformation from the memory 1004. The memory 1004 may include anon-removable memory and/or a removable memory, as described herein.

The input device 1000 may include a communications circuit 1008 fortransmitting and/or receiving information. The communications circuit1008 may transmit and/or receive information via wired and/or wirelesscommunications. The communications circuit 1008 may include atransmitter, an RF transceiver, or other circuit capable of performingwired and/or wireless communications. The communications circuit 1008may be in communication with control circuit 1002 for transmittingand/or receiving information. Though a single communications circuit1008 may be described, the input device 1000 may include multiplecommunication circuits each configured to transmit and/or receiveinformation.

The control circuit 1002 may also be in communication with one or moreinput circuit(s) 1006. The one or more of the input circuit(s) 1006 mayinclude an actuator (e.g., one or more buttons) for receiving input froma user. One or more of the input circuit(s) 1006 may include a sensingcircuit, such as an occupancy sensing circuit, a photosensing circuit, aline power sensing circuit (e.g., a line voltage sensing circuit and/ora line current sensing circuit), and/or a temperature sensing circuit,for example. The input circuit(s) 1006 may be configured for receivingand/or sensing information that may be sent to the control circuit 1002for further processing, such as configuration and/or control of anelectrical load. For example, the input circuit(s) 1006 may include anactuator that receives input from an actuation that is sent to thecontrol circuit 1002 to send control instructions to an electrical loador put the control circuit 1002 in an association mode and/orcommunicate association messages from the input device 1000. The inputcircuit(s) 1006 may include a sensing circuit capable of sensinginformation and sending the sensed information to the control circuit1002 for subsequent processing. For example, the input circuit(s) 1006may include a photosensing circuit capable of detecting light emissionfrom a lighting device or light source. The input circuit(s) 1006 mayinclude an occupancy sensing circuit that may include an infrared (IR)or visible light sensor circuit capable of detecting movement in aspace. The input circuit(s) 1006 may include a temperature sensingcircuit capable of detecting a temperature or change in temperaturewithin the space. The control circuit 1002 may receive information fromthe input circuit(s) 1006 (e.g. an indication that a button has beenactuated or sensed information) and may respond with a subsequentprocessing as described herein.

The input circuit(s) 1006 may include a line power sensing circuitcapable of detecting a change in power provided to an electrical load.For example, the line power sensing circuit may comprise a line voltagesensing circuit capable of detecting a change in voltage provided to theelectrical load and/or a line current sensing circuit capable ofdetecting a change in current supplied to the electrical load. Forexample, the line current sensing circuit may comprise a magneticsensing circuit (e.g., a Hall-effect sensing circuit) configured tosense magnetic fields caused by the current (e.g., a change in themagnitude of the current) supplied to the electrical load. For example,when the input device 1000 is a remote control device mounted over aactuator of a light switch (e.g., the remote control device 250 mountedover the toggle actuator 216 of the wall-mounted load control device210), the line current sensing circuit in the remote control device maybe configured to sense magnetic fields caused by the current (e.g., achange in the magnitude of the current) conducted through the lightswitch. The control circuit 1002 of the input device 1000 may beconfigured to detect a state change event to turn on the electrical loadin response to detecting, via the line current sensing circuit, a changein the magnitude of the current from a low magnitude (e.g., little or nocurrent flow) to a high magnitude. The magnitude of the current may bebelow a predefined threshold or above a predefined threshold to bedetected as a state change event (e.g., off or on). The control circuit1002 of the input device 1000 may be configured to detect a state changeevent to turn off the electrical load in response to detecting, via theline current sensing circuit, a change in the magnitude of the currentfrom a high magnitude to a low magnitude.

Each of the circuits within the input device 1000 may be powered by oneor more power source(s) 1010. The one or more power source(s) 1010 mayinclude an AC power supply and/or DC power supply, for example. The DCpower supply may include a battery source for example. The input device1000 may shift to the DC power supply when the AC power supply isunavailable, such as during a power removal event, for example. Inanother example, the input device may be powered by a single powersource, such as the AC power supply.

FIG. 11 is a block diagram illustrating an example network device 1100as described herein. The network device 1100 may include the networkdevice 290, shown in FIGS. 2A-2D, for example. The network device 1100may include a control circuit 1102 for controlling the functionality ofthe network device 1100. The control circuit 1102 may include one ormore general purpose processors, special purpose processors,conventional processors, digital signal processors (DSPs),microprocessors, integrated circuits, a programmable logic device (PLD),application specific integrated circuits (ASICs), or the like. Thecontrol circuit 1102 may perform signal coding, data processing, powercontrol, input/output processing, or any other functionality thatenables the network device 1100 to perform as described herein. Thecontrol circuit 1102 may store information in and/or retrieveinformation from the memory 1104. The memory 1104 may include anon-removable memory and/or a removable memory. The non-removable memorymay include random-access memory (RAM), read-only memory (ROM), a harddisk, or any other type of non-removable memory storage. The removablememory may include a subscriber identity module (SIM) card, a memorystick, a memory card, or any other type of removable memory.

The network device 1100 may include a communications circuit 1108 fortransmitting and/or receiving information. The communications circuit1108 may perform wireless and/or wired communications. Thecommunications circuit 1108 may include an RF transceiver or othercircuit capable of performing wireless communications via an antenna.Communications circuit 1108 may be in communication with control circuit1102 for transmitting and/or receiving information. Though a singlecommunications circuit 1108 may be described, the network device 1100may include multiple communication circuits each configured to transmitand/or receive information.

The control circuit 1102 may also be in communication with a display1106 for providing information to a user. The processor 1102 and/or thedisplay 1106 may generate GUIs for being displayed on the network device1100. The display 1106 and the control circuit 1102 may be in two-waycommunication, as the display 1106 may include a touch screen capable ofreceiving information from a user and providing such information to thecontrol circuit 1102. The network device may also include an actuator1112 (e.g., one or more buttons) that may be actuated by a user tocommunicate user selections to the control circuit 1102.

Each of the circuits within the network device 1100 may be powered by apower source 1110. The power source 1110 may include an AC power supplyor DC power supply, for example. The power source 1110 may generate asupply voltage Vcc for powering the circuits within the network device1100.

FIG. 12 is a block diagram illustrating an example hub device 1200 asdescribed herein. The hub device 1200 may include a control circuit 1202for controlling the functionality of the hub device 1200. The controlcircuit 1202 may include one or more general purpose processors, specialpurpose processors, conventional processors, digital signal processors(DSPs), microprocessors, integrated circuits, a programmable logicdevice (PLD), application specific integrated circuits (ASICs), or thelike. The control circuit 1202 may perform signal coding, dataprocessing, power control, input/output processing, or any otherfunctionality that enables the hub device 1200 to perform as describedherein. The control circuit 1202 may store information in and/orretrieve information from the memory 1204. The memory 1204 may include anon-removable memory and/or a removable memory. The non-removable memorymay include random-access memory (RAM), read-only memory (ROM), a harddisk, or any other type of non-removable memory storage. The removablememory may include a subscriber identity module (SIM) card, a memorystick, a memory card, or any other type of removable memory.

The hub device 1200 may include a communications circuit 1206 fortransmitting and/or receiving information. The communications circuit1206 may perform wireless and/or wired communications. The hub device1200 may also, or alternatively, include a communications circuit 1208for transmitting and/or receiving information. The communicationscircuit 1206 may perform wireless and/or wired communications.Communications circuits 1206 and 1208 may be in communication withcontrol circuit 1202. The communications circuits 1206 and 1208 mayinclude RF transceivers or other communications circuits capable ofperforming wireless communications via an antenna. The communicationscircuit 1206 and communications circuit 1208 may be capable ofperforming communications via the same communication channels ordifferent communication channels. For example, the communicationscircuit 1206 may be capable of communicating (e.g., with a networkdevice, over a network, etc.) via a wireless communication channel(e.g., BLUETOOTH®, near field communication (NFC), WIFI®, WI-MAX®,cellular, etc.) and the communications circuit 1208 may be capable ofcommunicating (e.g., with control devices and/or other devices in theload control system) via another wireless communication channel (e.g.,WI-FI® or a proprietary communication channel, such as CLEAR CONNECT™).

The control circuit 1202 may be in communication with an LED indicator1212 for providing indications to a user. The control circuit 1202 mayalso be in communication with one or more input circuit(s) 1214. The oneor more of the input circuit(s) 1214 may include an actuator (e.g., oneor more buttons) for receiving input from a user. One or more of theinput circuit(s) 1214 may include a sensing circuit, such as anoccupancy sensing circuit, a photosensing circuit, a line power sensingcircuit, and/or a temperature sensing circuit, for example. The inputcircuit(s) 1214 may be configured for receiving and/or sensinginformation that may be sent to the control circuit 1202 for furtherprocessing, such as configuration and/or control of an electrical load.For example, the input circuit(s) 1214 may include an actuator thatreceives input from an actuation that is sent to the control circuit1202 to send control instructions to an electrical load or put thecontrol circuit 1202 in an association mode and/or communicateassociation messages from the hub device 1200. The input circuit(s) 1214may include a sensing circuit capable of sensing information and sendingthe sensed information to the control circuit 1202 for subsequentprocessing. For example, the input circuit(s) 1214 may include aphotosensing circuit capable of detecting light emission from a lightingdevice or light source. The input circuit(s) 1214 may include anoccupancy sensing circuit that may include an infrared (IR) or visiblelight sensor circuit capable of detecting movement in a space. The inputcircuit(s) 1214 may include a temperature sensing circuit capable ofdetecting a temperature or change in temperature within the space. Thecontrol circuit 1202 may receive information from the input circuit(s)1214 (e.g. an indication that a button has been actuated or sensedinformation) and may respond with a subsequent processing as describedherein.

Each of the circuits within the hub device 1200 may be powered by one ormore power source(s) 1210. The power source(s) 1210 may include an ACpower supply and/or a DC power supply, for example. The DC power supplymay include a battery source, for example. The hub device 1200 may shiftto the DC power supply when the AC power supply is unavailable, such asduring a power removal event, for example. In another example, the hubdevice 1200 may be powered by a single power source, such as the ACpower supply. The power source 1210 may generate a supply voltage Vccfor powering the circuits within the hub device 1200.

Although features and elements are described herein in particularcombinations, each feature or element can be used alone or in anycombination with the other features and elements. The methods describedherein may be implemented in a computer program, software, or firmwareincorporated in a computer-readable medium for execution by a computeror processor. Examples of computer-readable media include electronicsignals (transmitted over wired or wireless connections) andcomputer-readable storage media. Examples of computer-readable storagemedia include, but are not limited to, a read only memory (ROM), arandom access memory (RAM), removable disks, and optical media such asCD-ROM disks, and digital versatile disks (DVDs).

1. A control device comprising: a communication circuit; and a controlcircuit configured to: receive, from a sensing circuit, an indication ofa state change event turning on an electrical load, determine that theelectrical load lost power due to a system power removal event prior tothe indication of the state change event turning on the electrical load,and after the electrical load is determined to have lost power due tothe system power removal event that occurred prior to the indication ofthe state change event turning on the electrical load, transmit a firstcommand for controlling the electrical load via the communicationcircuit, wherein the first command is configured to set the electricalload to a previous state of the electrical load prior to the systempower removal event.
 2. The control device of claim 1, furthercomprising the sensing circuit, wherein the electrical load is alighting load, and wherein the sensing circuit is a photosensing circuitcapable of detecting light emission from the lighting load, and whereinthe indication of the state change event turning on the lighting loadcomprises a detection of a change in the light emission from thelighting load.
 3. The control device of claim 1, wherein the electricalload is a lighting load, wherein the sensing circuit is an externaldevice comprising a photosensing circuit capable of detecting lightemission from the lighting load, and wherein the indication of the statechange event turning on the lighting load comprises a message receivedfrom the external device based on the light emission from the lightingload.
 4. The control device of claim 1, further comprising the sensingcircuit, wherein the sensing circuit is a line current sensing circuitconfigured to detect a current conducted by the electrical load, andwherein the indication of the state change event turning on the lightingload comprises a change in the current being supplied to the electricalload.
 5. The control device of claim 1, wherein the control circuit isfurther configured to transmit, via the communication circuit, a queryto a hub device to determine the previous state of the electrical load.6. The control device of claim 1, wherein the control circuit isconfigured to determine that the electrical load lost power due to asystem power removal event by being configured to: receive an indicationof a state change event turning off the lighting load from the sensingcircuit, send a second message, in response to the indication of thestate change event turning off the lighting load, to a load controldevice configured to control the electrical load, and fail to receive aresponse to the second message within a timeout period of time.
 7. Thecontrol device of claim 6, wherein the control circuit is furtherconfigured to flag the electrical load as unpowered in a memory, whenthe response to the second message is not received from the load controldevice within the timeout period of time.
 8. The control device of claim1, wherein the control circuit is configured to store state informationin a memory and wherein the control circuit is further configured todetermine the previous state of the electrical load via the memory. 9.The control device of claim 1, wherein the control circuit beingconfigured to determine that the electrical load lost power due to asystem power removal event prior to the state change event turning onthe electrical load further comprises the control circuit beingconfigured to: send a query, in response to the indication of the statechange event turning on the electrical load, to a load control deviceconfigured to control the electrical load; and receive an indicationfrom the load control device, in response to the query, indicating thatthe electrical load lost power due to the system power removal eventprior to the state change event turning on the electrical load.
 10. Thecontrol device of claim 1, wherein the control circuit being configuredto determine that the electrical load lost power due to a system powerremoval event prior to the state change event turning on the electricalload further comprises the control circuit being configured to: send aquery, in response to the indication of the state change event turningon the electrical load, to a first load control device other than asecond load control device configured to control the electrical load;and receive an indication from the first load control device, inresponse to the query, indicating that a second electrical loadcontrollable by the first load control device lost power due to thesystem power removal event prior to the state change event turning onthe electrical load.
 11. The control device of claim 1, furthercomprising an actuator configured to receive a user input, wherein thecontrol circuit is configured to transmit a second command forcontrolling the electrical load in response to an actuation of theactuator.
 12. A method comprising: receiving, from a sensing circuit, anindication of a state change event turning on an electrical load;determining that the electrical load lost power due to a system powerremoval event prior to the indication of the state change event turningon the electrical load; and after the electrical load is determined tohave lost power due to the system power removal event that occurredprior to the indication of the state change event turning on theelectrical load, transmitting a first command for controlling theelectrical load via the communication circuit, wherein the first commandis configured to set the electrical load to a previous state of theelectrical load prior to the system power removal event.
 13. The methodof claim 12, wherein the electrical load is a lighting load, and whereinthe sensing circuit is a photosensing circuit capable of detecting lightemission from the lighting load.
 14. The method of claim 13, wherein thedetermination that the electrical load lost power is based on a digitalmessage from a device comprising the photosensing circuit.
 15. Themethod of claim 12, wherein the sensor is a line current sensing circuitconfigured to detect a current driven to the electrical load.
 16. Themethod of claim 12, further comprising transmitting a query to a hubdevice to determine the previous state of the electrical load, whereinthe previous state is a state of the electrical load prior to the systempower removal event.
 17. The method of claim 12, wherein the determiningthat the electrical load lost power due to a system power removal eventfurther comprises: receiving an indication of a state change eventturning off the electrical load from the sensor; sending a secondmessage, in response to the indication of the state change event turningoff the lighting load, to a load control device configured to controlthe electrical load; and failing to receive a response to the secondmessage within a timeout period of time.
 18. The method of claim 17,further comprising flagging the electrical load as unpowered when thepower removal event is determined to be a system power removal event.19. The method of claim 12, further comprising: storing stateinformation in memory; and determining the previous state of theelectrical load via the stored state information.
 20. The method ofclaim 12, wherein determining whether the electrical load lost power dueto a system power removal event further comprises: sending a query to aload control device configured to control the electrical load; andreceiving an indication from the load control device, in response to thequery, that the electrical load lost power due to a system power removalevent.
 21. A control device comprising: a photosensing circuit capableof detecting light emission from a lighting load; a communicationcircuit; and a control circuit configured to: receive, from thephotosensing circuit, an indication of a state change event turning onthe lighting load, wherein the indication of the state change event isreceived in response to a detection of a change in a lighting level fromthe lighting load; determine that the lighting load lost power due to asystem power removal event prior to the indication of the state changeevent turning on the lighting load, and after the lighting load isdetermined to have lost power due to the system power removal event thatoccurred prior to the indication of the state change event turning onthe lighting load, transmit a first command for controlling the lightingload via the communication circuit, wherein the first command isconfigured to set the lighting load to a previous state of the lightingload prior to the system power removal event.
 22. The control device ofclaim 21, wherein the control circuit is further configured to transmit,via the communication circuit, a query to a hub device to determine theprevious state of the lighting load.
 23. The control device of claim 21,wherein the control circuit is configured to determine that the lightingload lost power due to a system power removal event by being configuredto: receive an indication of a state change event turning off thelighting load from the photosensing circuit, send a second message, inresponse to the indication of the state change event turning off thelighting load, to a lighting control device configured to control thelighting load, and fail to receive a response to the second messagewithin a timeout period of time.
 24. The control device of claim 23,wherein the control circuit is further configured to flag the lightingload as unpowered in a memory, when the response to the second messageis not received from the load control device.
 25. The control device ofclaim 21, wherein the control circuit is configured to store stateinformation in a memory and wherein the control circuit is furtherconfigured to determine the previous state of the lighting load via thememory.
 26. The control device of claim 21, wherein the control circuitbeing configured to determine that the lighting load lost power due to asystem power removal event that occurred prior to the indication of thestate change event turning on the lighting load further comprises thecontrol circuit being configured to: send a query, in response to theindication of the state change event turning on the lighting load, to aload control device configured to control the lighting load; and receivean indication from the load control device, in response to the query,indicating that the lighting load lost power due to the system powerremoval event that occurred prior to the indication of the state changeevent turning on the lighting load.
 27. The control device of claim 21,further comprising an actuator configured to receive a user input,wherein the control circuit is configured to transmit a second commandfor controlling the lighting load in response to an actuation of theactuator.
 28. A control device comprising: a line power sensing circuitconfigured to detect a current conducted by an electrical load; acommunication circuit; and a control circuit configured to: receive,from the line current sensing circuit, an indication of a state changeevent turning on the electrical load, wherein the indication of thestate change event turning on the electrical load comprises a change inthe current being supplied to the electrical load, determine that theelectrical load lost power due to a system power removal event prior tothe indication of the state change event turning on the electrical load,and after the electrical load is determined to have lost power due tothe system power removal event that occurred prior to the indication ofthe state change event turning on the electrical load, transmit a firstcommand for controlling the electrical load via the communicationcircuit, wherein the first command is configured to set the electricalload to a previous state of the electrical load prior to the systempower removal event.
 29. The control device of claim 28, wherein thecontrol circuit is further configured to transmit, via the communicationcircuit, a query to a hub device to determine the previous state of theelectrical load.
 30. The control device of claim 28, wherein the controlcircuit is configured to determine that the electrical load lost powerdue to a system power removal event by being configured to: receive anindication of a state change event turning off the electrical load fromthe line power sensing circuit, send a second message, in response tothe indication of the state change event turning off the electricalload, to a lighting control device configured to control the electricalload, and fail to receive a response to the second message within atimeout period of time.
 31. The control device of claim 30, wherein thecontrol circuit is further configured to flag the electrical load asunpowered in a memory, when the response to the second message is notreceived from the load control device.
 32. The control device of claim28, wherein the control circuit is configured to store state informationin a memory, and wherein the control circuit is further configured todetermine the previous state of the electrical load via the memory. 33.The control device of claim 28, wherein the control circuit beingconfigured to determine that the electrical load lost power due to asystem power removal event that occurred prior to the indication of thestate change event turning on the electrical load comprises the controlcircuit being configured to: send a query, in response to the indicationof the state change event turning on the electrical load, to a loadcontrol device configured to control the electrical load; and receive anindication from the load control device, in response to the query,indicating that the electrical load lost power due to a system powerremoval event that occurred prior to the indication of the state changeevent turning on the electrical load.
 34. The control device of claim28, further comprising an actuator configured to receive a user input,wherein the control circuit is configured to transmit a second commandfor controlling the electrical load in response to an actuation of theactuator.